Search/ReVault flaws let hackers bypass Windows login on Dell laptops
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ReVault flaws let hackers bypass Windows login on Dell laptops

ControlVault3 firmware vulnerabilities impacting over 100 Dell laptop models can allow attackers to bypass Windows login and install malware that persists across system reinstalls. Dell ControlVault is a hardware-based security solution that stores passwords, biometric data, and security codes within firmware on a dedicated daughterboard, known as the Unified Security Hub (USH). The five vulnerabilities, reported by Cisco's Talos security division and dubbed "ReVault," affect both the ControlVault3 firmware and its Windows application programming interfaces (APIs) across Dell's business-focused Latitude and Precision laptop series. These devices are popular in cybersecurity, government, and industrial environments, where smartcards, fingerprints, and NFC are also commonly used for…

CVEs
5
Highest CVSS
8.8
In KEV
0
Sources
4
Key vulnerabilities
CVE-2025-25215CVSS 8.8

An arbitrary free vulnerability exists in the cv_close functionality of Dell ControlVault3 prior to 5.15.10.14 and Dell ControlVault3 Plus prior to 6.2.26.36. A specially crafted ControlVault API call can lead to an arbitrary free. An attacker can forge a fake session to trigger this vulnerability.

CVE-2025-25050CVSS 8.8

An out-of-bounds write vulnerability exists in the cv_upgrade_sensor_firmware functionality of Dell ControlVault3 prior to 5.15.10.14 and Dell ControlVault 3 Plus prior to 6.2.26.36. A specially crafted ControlVault API call can lead to an out-of-bounds write. An attacker can issue an API call to trigger this vulnerability.

CVE-2025-24922CVSS 8.8

A stack-based buffer overflow vulnerability exists in the securebio_identify functionality of Dell ControlVault3 prior to 5.15.10.14 and Dell ControlVault3 Plus prior to 6.2.26.36. A specially crafted malicious cv_object can lead to a arbitrary code execution. An attacker can issue an API call to trigger this vulnerability.

CVE-2025-24311CVSS 8.4

An out-of-bounds read vulnerability exists in the cv_send_blockdata functionality of Dell ControlVault3 prior to 5.15.10.14 and Dell ControlVault3 Plus prior to 6.2.26.36. A specially crafted ControlVault API call can lead to an information leak. An attacker can issue an API call to trigger this vulnerability.

CVE-2025-24919CVSS 8.1

A deserialization of untrusted input vulnerability exists in the cvhDecapsulateCmd functionality of Dell ControlVault3 prior to 5.15.10.14 and ControlVault3 Plus prior to 6.2.26.36. A specially crafted ControlVault response to a command can lead to arbitrary code execution. An attacker can compromise a ControlVault firmware and have it craft a malicious response to trigger this vulnerability.

Connections
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11th August – Threat Intelligence Report
For the latest discoveries in cyber research for the week of 11th August, please download our Threat Intelligence Bulletin. TOP ATTACKS AND BREACHES Air France has experienced a data breach that resulted in unauthorized access to customer data through a compromised external customer service platform. The attack exposed personal information, including names, email addresses, phone numbers, frequent flyer program details, and recent transactions, but did not affect customer financial or sensitive personal data. Google has suffered a data breach that resulted in the exposure of approximately 2.55 million business contact records from its Salesforce CRM, including business names, phone numbers, and sales notes of potential Google Ads customers. The attack is linked to ShinyHunters and possibly to Scattered Spider, who extorted Google and threatened to leak the stolen data. Bouygues Telecom, a French internet service provider, has confirmed a cyberattack that resulted in unauthorized access to personal data from 6.4 million customer accounts. The data breach affected a segment of its mobile and fiber-to-the-home customers, exposing limited personal data. Pandora, a Danish jewelry manufacturer and retailer, has suffered a data breach that resulted in the theft of customer names, birthdates, and email addresses from its Salesforce database. The breach impacted the personal information of customers, but no passwords, IDs, or financial data were exposed. The US Federal Judiciary has confirmed a cyber attack that resulted in unauthorized access to its electronic case management systems, exposing confidential court documents including sensitive sealed filings and potentially the identities of confidential informants. American Public Broadcasting Service (PBS) has suffered a data breach that resulted in the exposure of corporate contact information for 3,997 employees and affiliates, including names, corporate emails, job titles, departments, locations, hobbies, and supervisor names. Pakistan Petroleum Limited (PPL) has experienced a cyber-attack that resulted in its IT systems being crippled, with servers encrypted, backups blocked, and financial operations suspended for two days. Vital data—encompassing operational records, contracts, and employee information—was exfiltrated and is now being held hostage. Blue Locker claimed responsibility for the attack. The University of Western Australia has suffered a data breach that resulted in unauthorized access to password information of thousands of staff members and students. The incident forced a lockout of all users and mandatory password resets, with no evidence that any other data or systems were compromised. VULNERABILITIES AND PATCHES Check Point Research has identified a persistent remote code execution vulnerability in the Cursor IDE, tracked as CVE-2025-54136. The vulnerability is caused by insufficient validation of Model Context Protocol (MCP) configuration changes. After a user’s initial approval of a benign MCP plugin, attackers with write access can modify MCP commands to execute arbitrary or malicious code on victims’ machines each time the project is opened, without any further prompts or interaction. Cisco has disclosed five critical vulnerabilities in Dell ControlVault3 firmware and its associated Windows APIs, collectively named “ReVault.” These flaws (CVE-2025-24311, CVE-2025-25050, CVE-2025-25215, CVE-2025-24922, CVE-2025-24919) enable attackers to achieve arbitrary code execution, persistent firmware implants, and privilege escalation, potentially bypassing Windows authentication and persisting across OS reinstalls. Trend Micro has released an advisory addressing vulnerabilities CVE-2025-54987 and CVE-2025-54948, two critical severity Remote Code Execution vulnerabilities (9.4 CVSS) in Trend Micro Apex One management console. The vulnerabilities have been actively exploited in the wild. THREAT INTELLIGENCE REPORTS Researchers have analyzed recent updates to Raspberry Robin, a sophisticated malware downloader active since 2021, revealing advanced obfuscation techniques and improvements in network encryption, such as a transition from AES-CTR to ChaCha-20 and the introduction of per-request randomized counters and nonces. The malware now utilizes obfuscated stack pointers, complex initialization loops to hinder brute-force decryption, modified RC4 key structures, and employs a new local privilege escalation exploit (CVE-2024-38196). Check Point Threat Emulation and Harmony Endpoint provide protection against this threat (Trojan.Wins.RaspberryRobin.ta.*, Trojan.Wins.RaspberryRobin.*) Researchers have uncovered a novel AV-killer malware abusing the legitimate ThrottleStop.sys driver (CVE-2025-7771), used in the wild since at least October 2024. This malware, delivered alongside the vulnerable driver, leverages two exposed IOCTL interfaces to perform arbitrary physical memory reads and writes via MmMapIoSpace, enabling privileged kernel-level calls to locate and terminate a wide range of antivirus and EDR processes. Ukrainian Computer Emergency Response Team (CERT-UA) has analyzed a wave of cyber-espionage attacks by UAC-0099, leveraging a court-summons phishing lure. These attacks begin with phishing emails sent via UKR.NET that deliver HTA files containing obfuscated VBScript, which drop files, create scheduled tasks, and deploy the MATCHBOIL C# loader—followed by the MATCHWOK backdoor and DRAGSTARE stealer.
research.checkpoint.comAug 11, 2025extracted
Week in review: SonicWall firewalls targeted in ransomware attacks, Black Hat USA 2025
Week in review: SonicWall firewalls targeted in ransomware attacks, Black Hat USA 2025 Here’s an overview of some of last week’s most interesting news, articles, interviews and videos: Black Hat USA 2025 Black Hat USA 2025 took place at the Mandalay Bay Convention Center in Las Vegas. Explore related news, photos, product releases, and more. AIBOMs are the new SBOMs: The missing link in AI risk management In this Help Net Security interview, Marc Frankel, CEO at Manifest Cyber, discusses how overlooked AI-specific risks, like poisoned training data and shadow AI, can lead to security issues that conventional tools fail to detect. He explains how AI Bills of Materials (AIBOMs) extend SBOMs to provide transparency into datasets, model weights, and third-party integrations, improving governance and incident response. Security tooling pitfalls for small teams: Cost, complexity, and low ROI In this Help Net Security interview, Aayush Choudhury, CEO at Scrut Automation, discusses why many security tools built for large enterprises don’t work well for leaner, cloud-native teams. He explains how simplicity, integration, and automation are key for SMBs with limited resources. Beyond PQC: Building adaptive security programs for the unknown In this Help Net Security interview, Jordan Avnaim, CISO at Entrust, discusses how to communicate the quantum computing threat to executive teams using a risk-based approach. He explains why post-quantum cryptography (PQC) is an urgent and long-term priority. SonicWall firewalls targeted in ransomware attacks, possibly via zero-day Attackers wielding the Akira ransomware and possibly a zero-day exploit have been spotted targeting SonicWall firewalls since July 15, 2025. Project Ire: Microsoft’s autonomous malware detection AI agent Microsoft is working on a AI agent whose main goal is autonomous malware detection and the prototype – dubbed Project Ire – is showing great potential, the company has announced on Tuesday. Millions of Dell laptops could be persistently backdoored in ReVault attacks A set of firmware vulnerabilities affecting 100+ Dell laptop models widely used in government settings and by the cybersecurity industry could allow attackers to achieve persistent access even across Windows reinstalls, Cisco Talos researchers have discovered. Trend Micro Apex One flaws exploted in the wild (CVE-2025-54948, CVE-2025-54987) Unauthenticated command injection vulnerabilities (CVE-2025-54948, CVE-2025-54987) affecting the on-premise version of Trend Micro’s Apex One endpoint security platform are being probed by attackers, the company has warned on Wednesday. Adobe patches critical Adobe Experience Manager Forms vulnerabilities with public PoC Adobe has released an emergency security update for Adobe Experience Manager Forms on Java Enterprise Edition (JEE), which fix two critical vulnerabilities (CVE-2025-54253, CVE-2025-54254) with a publicly available proof-of-concept (PoC) exploit. Microsoft urges admins to plug severe Exchange security hole (CVE-2025-53786) The privilege escalation can be performed by exploiting CVE-2025-53786, a newly disclosed vulnerability that stems from Exchange Server and Exchange Online sharing the same service principal – i.e., the Office 365 Exchange Online application – in hybrid configurations. (The app is used to authenticate and secure the communication between Exchange Server and Exchange Online.) Cybersecurity and the development of software-defined vehicles In many automotive companies, the same systems-engineering teams are responsible for both safety and security. As a result, cybersecurity is treated as a subset of safety, undergirded by an implicit assumption: “If it’s safe, it must be secure.” What GPT‑5 means for IT teams, devs, and the future of AI at work OpenAI has released GPT‑5, the newest version of its large language model. It’s now available to developers and ChatGPT users, and it brings some real changes to how AI can be used in business and IT environments. August 2025 Patch Tuesday forecast: Try, try again July started slow with a calm Patch Tuesday, addressing 130 CVEs but only one publicly disclosed, so risk was low. Then two SharePoint CVEs were exploited, heating things up with hotfixes late in the month. Add security issues in Microsoft Exchange and major Google and Apple updates, and July ended very active. Open-source password recovery utility Hashcat 7.0.0 released Hashcat is an open-source password recovery tool that supports five attack modes and more than 300 highly optimized hashing algorithms. It runs on CPUs, GPUs, and other hardware accelerators across Linux, Windows, and macOS, and includes features for distributed password cracking at scale. BloodHound 8.0 debuts with major upgrades in attack path management SpecterOps has released BloodHound 8.0, the latest iteration of its open-source attack path management platform, featuring major enhancements and expanded capabilities. Open-source server management platform Proxmox VE 9.0 released Proxmox Virtual Environment (VE) 9.0 introduces advancements in both storage and networking capabilities, addressing critical enterprise demands. AI in the SOC: Game-changer or more noise? In this Help Net Security video, Kev Marriott, Senior Manager of Cyber at Immersive Labs, explores the challenges and opportunities of integrating AI into Security Operations Centers (SOCs). Third-party partners or ticking time bombs? In this Help Net Security video, Ngaire Elizabeth Guzzetti, Technical Director Supply Chain at CyXcel, discusses why a third of U.S. organizations don’t trust third-party vendors to manage critical risks and what that means for supply chain security. What’s keeping risk leaders up at night? AI, tariffs, and cost cuts Enterprise risk leaders are most concerned about rising tariffs and trade tensions heading into the second half of 2025, according to a new report from Gartner. The firm’s second-quarter Emerging Risk Report, based on a survey of 223 senior risk, audit, and compliance executives, ranks the escalating trade war as the top emerging risk, up from third in the first quarter. The surprising truth about identity security confidence Organizations most confident in their identity security are often the least prepared, according to a new report from BeyondID. The study reveals a troubling gap between what organizations believe about their identity security programs and how they actually behave. Surprisingly, those expressing the highest confidence are adopting fewer best practices than their more cautious peers. Average global data breach cost now $4.44 million IBM released its Cost of a Data Breach Report, which revealed AI adoption is greatly outpacing AI security and governance. While the overall number of organizations experiencing an AI-related breach is a small representation of the researched population, this is the first time security, governance and access controls for AI have been studied in this report, which suggests AI is already an easy, high value target. Ransomware groups shift to quadruple extortion to maximize pressure Threat actors are using a new quadruple extortion tactic in ransomware campaigns, while double extortion remains the most common approach, according to Akamai. Your employees uploaded over a gig of files to GenAI tools last quarter In Q2 2025, Harmonic reviewed 1 million GenAI prompts and 20,000 uploaded files across more than 300 GenAI and AI-powered SaaS apps, and the findings confirm that sensitive data is being exposed through GenAI tools, something many security leaders fear but find difficult to measure. Why 90% of cyber leaders are feeling the heat 90% of cyber leaders find managing cyber risks harder today than five years ago, mainly due to the explosion of AI and expanding attack surfaces, according to BitSight. These threats are also fueling high rates of burnout, with 47% of cybersecurity and cyber risk professionals reporting exhaustion. CISOs say they’re prepared, their data says otherwise A new Axonius report, based on a survey of 500 U.S.-based IT and security leaders, shows a disconnect between perceived readiness and actual performance in vulnerability and exposure management. While 90% of respondents said their organization is prepared to act when a threat is found, only 25% said they trust the data in their security tools. Ransomware is up, zero-days are booming, and your IP camera might be next Cyber attackers are finding new ways in through the overlooked and unconventional network corners. Forescout’s 2025H1 Threat Review reveals a surge in advanced tactics, with zero-day exploits up 46 percent and ransomware attacks averaging 20 per day. Energy companies are blind to thousands of exposed services Many of America’s largest energy providers are exposed to known and exploitable vulnerabilities, and most security teams may not even see them, according to a new report from SixMap. AI can write your code, but nearly half of it may be insecure While GenAI excels at producing functional code, it introduces security vulnerabilities in 45 percent of cases, according to Veracode’s 2025 GenAI Code Security Report, which analyzed code produced by over 100 LLMs across 80 real-world coding tasks. Cybercriminals are getting personal, and it’s working Cybercriminals are deploying unidentifiable phishing kits (58% of phishing sites) to propagate malicious campaigns at scale, indicating a trend towards custom-made or obfuscated deployments, according to VIPRE Security. Fraud controls don’t guarantee consumer trust Over a third of companies say they are using AI, including generative AI, to fight fraud, according to Experian. As fraud threats become more complex, companies are accelerating their investments with over half adopting new analytics and building AI models to enhance customer decision-making. From fake CAPTCHAs to RATs: Inside 2025’s cyber deception threat trends Cybercriminals are getting better at lying. That’s the takeaway from a new LevelBlue report, which outlines how attackers are using social engineering and legitimate tools to quietly move through environments before they’re caught. Back to basics webinar: The ecosystem of CIS Security best practices Watch this on-demand webinar to understand how you can use an ecosystem of security best practices built by the Center for Internet Security (CIS) to support this mission. Cybersecurity jobs available right now: August 5, 2025 We’ve scoured the market to bring you a selection of roles that span various skill levels within the cybersecurity field. Check out this weekly selection of cybersecurity jobs available right now. New infosec products of the week: August 8, 2025 Here’s a look at the most interesting products from the past week, featuring releases from Black Kite, Descope, Elastic, ExtraHop, LastPass, and Riverbed.
helpnetsecurity.comAug 10, 2025extracted
ReVault flaws let hackers bypass Windows login on Dell laptops
ControlVault3 firmware vulnerabilities impacting over 100 Dell laptop models can allow attackers to bypass Windows login and install malware that persists across system reinstalls. Dell ControlVault is a hardware-based security solution that stores passwords, biometric data, and security codes within firmware on a dedicated daughterboard, known as the Unified Security Hub (USH). The five vulnerabilities, reported by Cisco's Talos security division and dubbed "ReVault," affect both the ControlVault3 firmware and its Windows application programming interfaces (APIs) across Dell's business-focused Latitude and Precision laptop series. These devices are popular in cybersecurity, government, and industrial environments, where smartcards, fingerprints, and NFC are also commonly used for authentication. The complete list of ReVault vulnerabilities includes out-of-bounds flaws (CVE-2025-24311, CVE-2025-25050), an arbitrary free vulnerability (CVE-2025-25215), a stack overflow (CVE-2025-24922, and an unsafe deserialization issue (CVE-2025-24919) affecting ControlVault's Windows APIs. Dell has released security updates to address the ReVault flaws in the ControlVault3 driver and firmware between March and May. The full list of impacted models is available in Dell's security advisory. Windows login bypass and privilege escalation Chaining these vulnerabilities can allow attackers to gain arbitrary code execution on the firmware, potentially creating persistent implants that survive Windows reinstalls. They can also leverage physical access to bypass Windows login or escalate local user privileges to the administrator level. "A local attacker with physical access to a user's laptop can pry it open and directly access the USH board over USB with a custom connector," Cisco Talos said. "From there, all the vulnerabilities described previously become in-scope for the attacker without requiring the ability to log-in into the system or knowing a full-disk encryption password." Successful exploitation can also enable attackers to manipulate fingerprint authentication, forcing the targeted device to accept any fingerprint rather than only those of legitimate users. Talos recommends keeping systems updated through Windows Update or Dell's website, disabling unused security peripherals like fingerprint readers, smart card readers, and NFC readers, and disabling fingerprint login in high-risk situations. To mitigate some of the physical attacks, the researchers also suggested enabling chassis intrusion detection in computer BIOS settings to flag physical tampering attempts and Enhanced Sign-in Security (ESS) in Windows to detect inappropriate CV firmware. Overall prevention scores can hide what happens after initial access. Once attackers are using valid credentials, prevention drops sharply. The Blue Report 2026 measures defenses technique by technique across 338 million simulations run in customer production environments. Get the report
bleepingcomputer.comAug 6, 2025extracted
Flaws Expose 100 Dell Laptop Models to Implants, Windows Login Bypass
Five vulnerabilities in the ControlVault3 firmware and the associated Windows APIs expose millions of Dell laptops to persistent implants and Windows login bypasses via physical access, Cisco Talos reports. The issues, tracked as CVE-2025-24311, CVE-2025-25215, CVE-2025-24922, CVE-2025-25050, and CVE-2025-24919, were initially disclosed on June 13, when Dell announced that patches for them were rolled out for over 100 Dell Pro, Latitude, and Precision models. The affected component, ControlVault3 (and the ControlVault3+ iteration), is a hardware-based system meant to securely store passwords, biometric information, and security codes. CVE-2025-24311 and CVE-2025-25050 are out-of-bounds issues that could be triggered via specially crafted ControlVault API calls to leak information or write outside the allocated memory, while CVE-2025-25215 leads to an arbitrary free via a crafted call and can be triggered via a forged session. CVE-2025-24922 and CVE-2025-24919, a stack-based buffer overflow bug and a deserialization of untrusted input vulnerability, can lead to arbitrary code execution. According to Talos, an attacker that does not have administrative privileges could interact with ControlVault via the associated API and execute arbitrary code on the firmware, leaking sensitive information affecting the security of the device, which could allow them to modify the firmware. “This creates the risk of a so-called implant that could stay unnoticed in a laptop’s CV firmware and eventually be used as a pivot back onto the system in the case of a threat actor’s post-compromise strategy,” Talos, which named the flaws ReVault, says. The security firm also notes that an attacker with physical access to the device could pry it open and access the USH board, allowing the attacker to exploit any of the five vulnerabilities without having to log in or know a full-disk encryption password. “Another interesting consequence of this scenario is that if a system is configured to be unlocked with the user’s fingerprint, it is also possible to tamper with the CV firmware to accept any fingerprint rather than only allowing a legitimate user’s,” Talos notes. According to Talos, the vulnerabilities could pose a serious threat to organizations in cybersecurity, government, and other sensitive industries, where strict login requirements increase the likelihood of ControlVault being used. Dell’s June advisory lists all the affected models and vulnerable firmware versions, as well as the dates when patches were released for them. Related: Lenovo Firmware Vulnerabilities Allow Persistent Implant Deployment Related: Flaws in Gigabyte Firmware Allow Security Bypass, Backdoor Deployment Related: Dell Says Data Leaked by Hackers Is Fake Related: Critical OpenWrt Flaw Exposes Firmware Update Server to Exploitation
securityweek.comAug 6, 2025extracted
Related Stories
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US Tops Hit List as 396 SharePoint Systems Compromised Globally
On July 19–20, 2025, various security companies and national CERTs published alerts about active exploitation of on-premise SharePoint servers. According to the reports, observed attacks did not require authentication, allowed attackers to gain full control over the infected servers, and were performed using an exploit chain of two vulnerabilities: CVE-2025-49704 and CVE-2025-49706, publicly named “ToolShell”. Additionally, on the same dates, Microsoft released out-of-band security patches for the vulnerabilities CVE-2025-53770 and CVE-2025-53771, aimed at addressing the security bypasses of previously issued fixes for CVE-2025-49704 and CVE-2025-49706. The release of the new, “proper” updates has caused confusion about exactly which vulnerabilities attackers are exploiting and whether they are using zero-day exploits. Kaspersky products proactively detected and blocked malicious activity linked to these attacks, which allowed us to gather statistics about the timeframe and spread of this campaign. Our statistics show that widespread exploitation started on July 18, 2025, and attackers targeted servers across the world in Egypt, Jordan, Russia, Vietnam, and Zambia. Entities across multiple sectors were affected: government, finance, manufacturing, forestry, and agriculture. While analyzing all artifacts related to these attacks, which were detected by our products and public information provided by external researchers, we found a dump of a POST request that was claimed to contain the malicious payload used in these attacks. After performing our own analysis, we were able to confirm that this dump indeed contained the malicious payload detected by our technologies, and that sending this single request to an affected SharePoint installation was enough to execute the malicious payload there. Our analysis of the exploit showed that it did rely on vulnerabilities fixed under CVE-2025-49704 and CVE-2025-49706, but by changing just one byte in the request, we were able to bypass those fixes. In this post, we provide detailed information about CVE-2025-49704, CVE-2025-49706, CVE-2025-53770, CVE-2025-53771, and one related vulnerability. Since the exploit code is already published online, is very easy to use, and poses a significant risk, we encourage all organizations to install the necessary updates. The exploit Our research started with an analysis of a POST request dump associated with this wave of attacks on SharePoint servers. We can see that this POST request targets the “/_layouts/15/ToolPane.aspx” endpoint and embeds two parameters: “MSOtlPn_Uri” and “MSOtlPn_DWP”. Looking at the code of ToolPane.aspx, we can see that this file itself does not contain much functionality and most of its code is located in the ToolPane class of the Microsoft.SharePoint.WebPartPages namespace in Microsoft.SharePoint.dll. Looking at this class reveals the code that works with the two parameters present in the exploit. However, accessing this endpoint under normal conditions is not possible without bypassing authentication on the attacked SharePoint server. This is where the first Microsoft SharePoint Server Spoofing Vulnerability CVE-2025-49706 comes into play. CVE-2025-49706 This vulnerability is present in the method PostAuthenticateRequestHandler, in Microsoft.SharePoint.dll. SharePoint requires Internet Information Services (IIS) to be configured in integrated mode. In this mode, the IIS and ASP.NET authentication stages are unified. As a result, the outcome of IIS authentication is not determined until the PostAuthenticateRequest stage, at which point both the ASP.NET and IIS authentication methods have been completed. Therefore, the PostAuthenticateRequestHandler method utilizes a series of flags to track potential authentication violations. A logic bug in this method enables an authentication bypass if the “Referrer” header of the HTTP request is equal to “/_layouts/SignOut.aspx”, “/_layouts/14/SignOut.aspx”, or “/_layouts/15/SignOut.aspx” using case insensitive comparison. The code displayed in the image above handles the sign-out request and is also triggered when the sign-out page is specified as the referrer. When flag6 is set to false and flag7 is set to true, both conditional branches that could potentially throw an “Unauthorized Access” exception are bypassed. On July 8, 2025, Microsoft released an update that addressed this vulnerability by introducing additional checks to detect the usage of the “ToolPane.aspx” endpoint with the sign-out page specified as the referrer. The added check uses case insensitive comparison to verify if the requested path ends with “ToolPane.aspx”. Is it possible to bypass this check, say, by using a different endpoint? Our testing has shown that this check can be easily bypassed. CVE-2025-53771 We were able to successfully bypass the patch for vulnerability CVE-2025-49706 by adding just one byte to the exploit POST request. All that was required to bypass this patch was to add a “/” (slash) to the end of the requested “ToolPane.aspx” path. On July 20, 2025, Microsoft released an update that fixed this bypass as CVE-2025-53771. This fix replaces the “ToolPane.aspx” check to instead check whether the requested path is in the list of paths allowed for use with the sign-out page specified as the referrer. This allowlist includes the following paths: “/_layouts/15/SignOut.aspx”, “/_layouts/15/1033/initstrings.js”, “/_layouts/15/init.js”, “/_layouts/15/theming.js”, “/ScriptResource.axd”, “/_layouts/15/blank.js”, “/ScriptResource.axd”, “/WebResource.axd”, “/_layouts/15/1033/styles/corev15.css”, “/_layouts/15/1033/styles/error.css”, “/_layouts/15/images/favicon.ico”, “/_layouts/15/1033/strings.js”, “/_layouts/15/core.js”, and it can contain additional paths added by the administrator. While testing the CVE-2025-49706 bypass with the July 8, 2025 updates installed on our SharePoint debugging stand, we noticed some strange behavior. Not only did the bypass of CVE-2025-49706 work, but the entire exploit chain did! But wait! Didn’t the attackers use an additional Microsoft SharePoint Remote Code Execution Vulnerability CVE-2025-49704, which was supposed to be fixed in the same update? To understand why the entire exploit chain worked in our case, let’s take a look at the vulnerability CVE-2025-49704 and how it was fixed. CVE-2025-49704 CVE-2025-49704 is an untrusted data deserialization vulnerability that exists due to improper validation of XML content. Looking at the exploit POST request, we can see that it contains two URL encoded parameters: “MSOtlPn_Uri” and “MSOtlPn_DWP”. We can see how they are handled by examining the code of the method GetPartPreviewAndPropertiesFromMarkup in Microsoft.SharePoint.dll. A quick analysis reveals that “MSOtlPn_Uri” is a page URL that might be pointing to an any file in the CONTROLTEMPLATES folder and the parameter “MSOtlPn_DWP” contains something known as WebPart markup. This markup contains special directives that can be used to execute safe controls on a server and has a format very similar to XML. While this “XML” included in the “MSOtlPn_DWP” parameter does not itself contain a vulnerability, it allows attackers to instantiate the ExcelDataSet control from Microsoft.PerformancePoint.Scorecards.Client.dll with CompressedDataTable property set to malicious payload and trigger its processing using DataTable property getter. Looking at the code of the ExcelDataSet’s DataTable property getter in Microsoft.PerformancePoint.Scorecards.Client.dll, we find the method GetObjectFromCompressedBase64String, responsible for deserialization of CompressedDataTable property contents. The data provided as Base64 string is decoded, unzipped, and passed to the BinarySerialization.Deserialize method from Microsoft.SharePoint.dll. Attackers use this method to provide a malicious DataSet whose deserialized content is shown in the image above. It contains an XML with an element of dangerous type "System.Collections.Generic.List1[[System.Data.Services.Internal.ExpandedWrapper2[...], System.Data.Services, Version=4.0.0.0, Culture=neutral, PublicKeyToken=b77a5c561934e089]]", which allows attackers to execute arbitrary methods with the help of the well-known ExpandedWrapper technique aimed at exploitation of unsafe XML deserialization in applications based on the .NET framework. In fact, this shouldn’t be possible, since BinarySerialization.Deserialize in Microsoft.SharePoint.dll uses a special XmlValidator designed to protect against this technique by checking the types of all elements present in the provided XML and ensuring that they are on the list of allowed types. However, the exploit bypasses this check by placing the ExpandedWrapper object into the list. Now, to find out why the exploit worked on our SharePoint debugging stand with the July 8, 2025 updates installed, let’s take a look at how this vulnerability was fixed. In this patch, Microsoft did not really fix the vulnerability but only mitigated it by adding the new AddExcelDataSetToSafeControls class to the Microsoft.SharePoint.Upgrade namespace. This class contains new code that modifies the web.config file and marks the Microsoft.PerformancePoint.Scorecards.ExcelDataSet control as unsafe. Because SharePoint does not execute this code on its own after installing updates, the only way to achieve the security effect was to manually run a configuration upgrade using the SharePoint Products Configuration Wizard tool. Notably, the security guidance for CVE-2025-49704 does not mention the need for this step, which means at least some SharePoint administrators may skip it. Meanwhile, anyone who installed this update but did not manually perform a configuration upgrade remained vulnerable. CVE-2025-53770 On July 20, 2025, Microsoft released an update with a proper fix for the CVE-2025-49704 vulnerability. This patch introduces an updated XmlValidator that now properly validates element types in XML, preventing exploitation of this vulnerability without requiring a configuration upgrade and, more importantly, addressing the root cause and preventing exploitation of the same vulnerability through controls other than Microsoft.PerformancePoint.Scorecards.ExcelDataSet. CVE-2020-1147 Readers familiar with previous SharePoint exploits might feel that the vulnerability CVE-2025-49704/CVE-2025-53770 and the exploit used by the attackers looks very familiar and very similar to the older .NET Framework, SharePoint Server, and Visual Studio Remote Code Execution Vulnerability CVE-2020-1147. In fact, if we compare the exploit for CVE-2020-1147 and an exploit for CVE-2025-49704/CVE-2025-53770, we can see that they are almost identical. The only difference is that in the exploit for CVE-2025-49704/CVE-2025-53770, the dangerous ExpandedWrapper object is placed in the list. This makes CVE-2025-53770 an updated fix for CVE-2020-1147. Conclusions Despite the fact that patches for the ToolShell vulnerabilities are now available for deployment, we assess that this chain of exploits will continue being used by attackers for a long time. We have been observing the same situation with other notorious vulnerabilities, such as ProxyLogon, PrintNightmare, or EternalBlue. While they have been known for years, many threat actors still continue leveraging them in their attacks to compromise unpatched systems. We expect the ToolShell vulnerabilities to follow the same fate, as they can be exploited with extremely low effort and allow full control over the vulnerable server. To stay better protected against threats like ToolShell, we as a community should learn lessons from previous events in the industry related to critical vulnerabilities. Specifically, the speed of applying security patches nowadays is the most important factor when it comes to fighting such vulnerabilities. Since public exploits for these dangerous vulnerabilities appear very soon after vulnerability announcements, it is paramount to install patches as soon as possible, as a gap of even a few hours can make a critical difference. At the same time, it is important to protect enterprise networks against zero-day exploits, which can be leveraged when there is no available public patch for vulnerabilities. In this regard, it is critical to equip machines with reliable cybersecurity solutions that have proven effective in combatting ToolShell attacks before they were publicly disclosed. Kaspersky Next with its Behaviour detection component proactively protects against exploitation of these vulnerabilities. Additionally, it is able to detect exploitation and the subsequent malicious activity. Kaspersky products detect the exploits and malware used in these attacks with the following verdicts: UDS:DangerousObject.Multi.Generic PDM:Exploit.Win32.Generic PDM:Trojan.Win32.Generic HEUR:Trojan.MSIL.Agent.gen ASP.Agent.* PowerShell.Agent.*
11 shared
Jul 31, 2025
US Tops Hit List as 396 SharePoint Systems Compromised Globally
Check Point Research (CPR) conducted a focused analysis of Storm-2603, a threat actor associated with recent ToolShell exploitations, together with other Chinese APT groups. Storm-2603 utilizes a custom malware Command and Control (C2) framework dubbed internally by the attacker as “ak47c2”. This framework includes at least two different types of clients: HTTP-based (dubbed by us “ak47http”) and DNS-based (dubbed by us “ak47dns”). Based on VirusTotal data, Storm-2603 likely targeted some organizations in Latin America throughout the first half of 2025, in parallel to attacking organizations in APAC. Some of the actor’s TTPs align with many other ransomware groups, and involve open-source tools such as PsExec and masscan. In addition, the threat actors use a custom tool that leverages the BYOVD (Bring Your Own Vulnerable Driver) technique to tamper with endpoint protections. Storm-2603 attacks involved multiple ransomware families, sometimes bundled together. Those are commonly deployed by abusing DLL hijacking. Check Point Research (CPR) has been closely monitoring the ongoing exploitation of a group of Microsoft SharePoint Server vulnerabilities collectively referred to as “ToolShell.” These active attacks leverage four vulnerabilities—CVE-2025-49704, CVE-2025-49706, CVE-2025-53770, and CVE-2025-53771—and are attributed to multiple China affiliated threat actors. Among the threat groups identified by Microsoft, two are known APTs: Linen Typhoon (aka APT27) and Violet Typhoon (aka APT31). Another group is a newly observed, previously undocumented cluster called Storm-2603. While Microsoft linked this cluster’s activity to potential ransomware deployment, it was unable to assess the group’s objectives. As part of our ongoing investigation into ToolShell and its associated risks, we launched a targeted effort to better understand and characterize the threat posed by Storm-2603. Throughout our analysis, we uncovered several files likely tied to Storm-2603 intrusions, offering new insights that correspond to Microsoft’s description of the group. In this publication, we provide an in-depth examination of Storm-2603’s tactics, techniques, and procedures (TTPs), along with a technical breakdown of the ak47c2, a custom malware framework used in their attacks and their different ransomware payloads. Storm-2603 was first mentioned by Microsoft during investigations into a set of attacks on Microsoft SharePoint servers, known as the “ToolShell” campaign. While some activity was tied to known Chinese affiliated groups like Linen Typhoon (APT27) and Violet Typhoon (APT31), Storm-2603 appeared as a new, previously unreported actor. Microsoft linked the group to Lockbit and Warlock ransomware use. Figure 1 – Events associated with Storm-2603. Microsoft’s report provided only limited information about Storm-2603, including some of the TTPs associated with it, most of them quite generic. In addition, some of the reported indicators of compromise (IOCs) helped us uncover additional artifacts associated with previous Storm-2603 intrusions. One domain in particular, update.updatemicfosoft[.]com, linked to Storm-2603’s SharePoint exploitation, turned out to have been used in earlier campaigns dating back to March 2025. In those operations, it served as a C2 server for both DNS tunneling malware and an HTTP backdoor and was part of infrastructure used to deliver LockBit Black and Warlock/x2anylock ransomware. Our search for cases where the IOCs reported by Microsoft, revealed two incidents in which LockBit Black and WarLock ransomware variants were deployed together, in addition to multiple other tools, mostly open-source. In April 2025, a RAR archive named Evidencia.rar was uploaded to VirusTotal. The archive contains several artifacts likely extracted from compromised machines in a Storm-2603 case in a LATAM country. The artifacts in the archive provide a look at some of the open-source tools used by the actors in the intrusions which correlates with previous knowledge of the group: WinPcap – Captures and filters network traffic on Windows. PsExec – Executes commands on remote Windows systems. SharpHostInfo – Collects host and domain info on Windows environments. nxc – Exploits common vulnerabilities in network services. In addition to the open-source tools, the archive also contains the custom backdoor used by the group, as well as its unique ransomware payloads. dnsclient.exe – A custom backdoor utilized by Storm-2603 that communicates over DNS tunneling with update.updatemicfosoft[.]com, a domain associated with the group. See the next section for our analysis of the backdoor. 7z.exe & 7z.dll – Legitimate 7z executable side-loading malicious 7z.dll delivering X2anylock (aka Warlock), a ransomware used by Storm-2603. bbb.msi – An installer which uses clink_x86.exe to side-load clink_dll_x86.dll, leading to the execution of LockBit Black ransomware. Another MSI file uploaded to VirusTotal in April used a similar deployment method, starting with the MSI installer to launch multiple ransomware strains simultaneously: Figure 2 – MSI Multi-Ransomware Deployment. The MSI relies on the following files: MpCmdRun.exe & Mpclient.dll – Warlock Ransomware, deployed via DLL-hijacking. clink_x86.exe & clink_dll_x86.dll – LockBit Black ransomware, deployed via DLL-hijacking. z.exe & z.dll – x2anylock ransomware, deployed via DLL-hijacking. VMToolsEng.exe – Custom Antivirus Terminator. ServiceMouse.sys – Vulnerable driver used by VMToolsEng.exe for killing Antivirus processes. log.exe – A list of Antivirus processes to kill. msi.bat – Executes VMToolsEng.exe. 1.bat – Executes all the needed executables and the MSI. We attributed two custom backdoors to Storm-2306, both of which appear to be part of the framework named AK47 C2 based on the shared PDB path: C:\Users\Administrator\Desktop\work\tools\ak47c2\. When executed, the program immediately hides its console window, determines the host computer name (defaulting to unknown.local if that fails), and builds a DNS‑based command‑and‑control payload. It chooses a random five-character session ID, such as H4T14, and prefixes it with 1 for task requests or 2 for result uploads (e.g., 1H4T14 or 2H4T14). Each element, such as the task/result tag, a size flag (a for “all” when the entire message fits into one request), and the computer name, is XOR‑encoded with the ASCII key “VHBD@H”, converted to hexadecimal, and concatenated with dots before being prepended to the C2 domain update.micfosoft[.]com. This what the overall query looks like: DNS TXT and MG (a mail group member record type) record lookups (DnsQuery_A) are used to transmit and retrieve data. If the C2 server is unreachable, the client simply receives error 9003 (DNS_ERROR_RCODE_NAME_ERROR). Otherwise, the response text is decoded from hex, XOR‑decrypted, and parsed for the delimiter “:::”, which separates metadata from the actual command string. Commands run under cmd.exe /c 2>&1; a built‑in directive sleep n pauses execution for n seconds. For outputs larger than 0xFF bytes, the backdoor fragments data into 63‑byte sub‑segments. Each DNS query then follows: HttpClient backdoor has the pdb path C:\Users\Administrator\Desktop\work\tools\ak47c2\httpclient-cpp\x64\Release\httpclient-cpp.pdb and uses plain HTTP instead of DNS for the C2. It is built as a 64‑bit console program that also immediately hides its window on launch. On start‑up, the malware gathers the host computer name (similar to the DNS version, it defaults to unknown.local), then builds a JSON object with the fields cmd, cmd_id, fqdn, result, and type. For a task request, the object looks like this: {"cmd":"","cmd_id":"","fqdn":" ","result":"","type":"task"} After the host executes a command, the result is sent back with type:”result”. Before transmission, the entire JSON blob is XOR‑encrypted with the ASCII key “VHBD@H”, converted to hexadecimal, and placed in the body of an HTTP POST to “/” with generic headers (Content‑Type: text/plain, Accept: */*). The C2 replies with a similarly encoded JSON where the cmd field contains the next command. The implant executes it via cmd.exe /c 2>&1 and returns the output. We identified that during these attacks, several types of ransomware were deployed simultaneously. One is regular LockBit Black, and the second uses the.x2anylock extension. This extension was later used by the Warlock ransomware operator, mentioned in Microsoft’s report on the SharePoint exploitation. The Warlock ransom note is usually saved as How to decrypt my data.txt and looks like this: Figure 3 – Warlock Group ransom note. The ransom notes for all ransomware strains deployed by Storm-2603 are named How to decrypt my data.log (x2anylock) or .README.txt (LockBit Black) and have the same short content: Your decrypt ID: [redacted] Tox ID Support: 3DCE[redacted] Email Support: [redacted]@proton.me,[redacted]@proton.me,[redacted]@proton.me You can contact us in email or qtox. This ransom note’s name How to decrypt my data.log appeared in a recent LinkedIn post by Huntress, describing the case where multiple ransomware families were deployed together against the same target. While not a new tactic, this approach is rarely observed among established ransomware groups. An important part of the infection package described earlier is called Antivirus Terminator. It is a custom command line tool abusing a third-party signed legitimate driver to kill processes. From what we can see, it’s been in the wild since at least late 2024. The tool requires administrative privileges on the infected machine. The screenshot below shows how the listing is displayed in the console when the tool is run without parameters: Figure 4 – Antivirus Terminator supported arguments when run without parameters. The tool first creates a service called ServiceMouse, where the path to the service binary file is ServiceMouse.sys from the package. Next, the tool communicates with the installed service via IO control code 0x99000050, which is responsible for killing processes. The tool also has more capabilities, like deleting files and uninstalling drivers, and these use different IO control codes (0x990000D0 and 0x990001D0). Figure 6 – Antivirus Terminator kills process using third-party driver. The supplied third-party driver is a legitimate and signed component of Antiy System In-Depth Analysis Toolkit, originally named AToolsKrnl64.sys. The toolkit was developed by Antiy Labs, a Chinese security vendor, and features a graphical user interface that allows users, among others, to interact with and manipulate processes. The ability to kill processes is the most important feature which is abused by threat actors in this particular case. Figure 7 – Antiy System In-Depth Analysis Tookit GUI. The following piece of code in the driver handles the IO control code 0x99000050 mentioned above: Figure 8 – IO control code processing in the Antiy driver. The second function is the piece of code responsible for killing a process with a given PID. In this report we analyze Storm-2603, a relatively new threat actor first mentioned by Microsoft during investigations into the “ToolShell” campaign targeting SharePoint servers. While some of the exploitation activity was tied to known Chinese APT groups, Storm-2603 stood out as a previously undocumented group linked to ransomware deployment. By examining infrastructure indicators shared in public reporting, we were able to connect this actor to earlier campaigns involving LockBit Black and Warlock/X2anylock ransomware, dating back to at least March 2025. These earlier attacks used similar infrastructure and tools, including DNS tunneling and HTTP-based backdoors. Interestingly, multiple ransomware variants were deployed in the same attack. This behavior, along with the overlap in techniques, helps us better understand how Storm-2603 operates “The Turkish Rat” Evolved Adwind in a Massive Ongoing Phishing Campaign Check Point Research Publications August 11, 2017 “The Next WannaCry” Vulnerability is Here Check Point Research Publications March 12, 2026 “Handala Hack” – Unveiling Group’s Modus Operandi SUBSCRIBE TO CYBER INTELLIGENCE REPORTS We value your privacy! BFSI uses cookies on this site. We use cookies to enable faster and easier experience for you. By continuing to visit this website you agree to our use of cookies.
11 shared
Aug 1, 2025
Worm armed 42 GitHub repos by hiding a payload too big to fail
Some attacks take real skill. Others just need someone to leave a door open. This week has both. Exposed passwords, old bugs still getting exploited, and trusted software doing things it shouldn't. There's a strange mix of clever tricks and careless mistakes. Hackers are borrowing trust from familiar apps, websites, and AI tools. Some are using AI to speed things up. Others are leaving their own attack files exposed. Not exactly careful work. Different stories, familiar weak spots. Here's what showed up this week. The threats change every week. Subscribe, and we’ll alert you when each new ThreatsDay Bulletin is out. PHP2Shell attacks persist WordPress security company Wordefence said it's not aware of any WordPress site compromised through PHP2Shell (CVE-2026-109618 and CVE-2026-109619) as of October 28, 2026. "We continue to see PHP2Shell-related requests across the more than 5 million sites we protect," it said. "Those requests show ongoing scanning and exploitation attempts; they do not show whether an attempt succeeded. Our site-cleaning and incident response teams have not handled a WordPress compromise attributed to these vulnerabilities." 40,573 secrets exposed Hudson Rock's investigation into the FortiBleed credential harvesting campaign has uncovered 975 newly identified domains and 40,573 exposed secrets, including 37,076 local-user records and 1,576 Active Directory LDAP bind records. The data comes from newly obtained 1,703 FortiGate source files associated with 1,689 host identifiers. "The configuration material dates to around February 2026, earlier than the likely May/June material examined in the first investigation," Hudson Rock said. The latest discovery has been codenamed FortiBleed 2.0. Institutional DNS hijacked Threat actors have used domain shadowing to place illegal gambling content beneath legitimate school and government domains in two unrelated operations. "In both cases, an unauthorized party appears to have gained access to DNS administration and created records that the original domain owners may not have noticed," Infoblox said. "Because the resulting hostnames sat within established institutional namespaces, they provided especially useful infrastructure for search-engine optimization (SEO) and traffic acquisition." One cluster, linked to a threat actor called Hidden Hawk, has been found to add individual CNAME records that mapped institutional hostnames to gambling pages hosted largely on Cloudflare Pages. The second campaign exploiting an Indian government domain "delegated entire subzones to third-party authoritative nameservers and used a wildcard, allowing many hostnames to be managed outside the victim's DNS environment." Put differently, the unauthorized DNS access creates new institutional hostnames, which resolve to infrastructure serving illegal gambling doorway pages. The pages also leverage the established reputation of school and government namespaces to ensure that the malicious URLs show up prominently in search engine results. AI banking credential warning Bank of America is reminding customers not to share banking credentials with AI agents. In an email blast to customers titled "Protecting your finances in the AI World," the financial institution urged customers to never share their username and password with another person or an outside service, "including an AI-enabled tool or agent that offers to act on your behalf." Android tightens contact access Google has announced that an upcoming Android release will no longer be able to directly write to contacts with the WRITE_CONTACTS permission. "Instead, you can use the standard contact intents (ACTION_INSERT, ACTION_EDIT, and ACTION_INSERT_OR_EDIT)," Google said. "Currently, if your app needs to save even one contact, you might be requesting WRITE_CONTACTS. But that permission grants broad access, allowing an app to make widespread changes to contacts across the device in the background, even without user interaction. Most apps don’t need such broad permission." 26,400 live credentials exposed A scan of 7.25 million public repositories on Gitee, China's largest indigenous Git hosting platform, has uncovered 26,400 unique verified-live credentials, including an active organization-admin credential for a major enterprise AI platform and thousands of live cloud provider access keys, independent security researcher Ben Zimmermann said. Critical Fortinet fixes released Fortinet has released a "coordinated set of security updates for FortiOS, FortiManager, and FortiAnalyzer" to address critical and high-severity flaws that were flagged using an AI-assisted vulnerability discovery approach. Details of the issues are being kept under wraps until November 10, 2026. With Fortinet devices becoming a favorite target for attackers, it's essential that users move quickly to apply the fixes. Zero-permission token theft Details have emerged about a now-patched flaw in Microsoft Authenticator (CVE-2026-80097 aka AuthMask) that could be exploited by installing and running a malicious application on an affected Android device and convincing the user to complete an authentication flow in the app by claiming to be a trusted app and getting the corresponding tokens. The flaw could be exploited to take over work accounts without requiring additional permissions. "Successful exploitation could allow the attacker to obtain authentication tokens and access resources as the affected user," Microsoft said. According to Enclave, "an unprivileged Android app with zero permissions could impersonate any installed Microsoft first-party app and have the Microsoft Authenticator broker hand it that app's tokens. The setup is a device with Authenticator installed and one work account signed into it." 32 fake AI bots hunt secrets Attackers are disguising themselves as AI agents to steal credentials. Cequence said it has tracked a single actor running AI agent impersonation at scale by posing as about 32 different AI bots, including ChatGPT, Claude, and Perplexity, while searching for passwords, API keys, and cloud credentials. "The malicious scanner runs from a major cloud provider and rotates through about 32 AI bot identities, spanning crawlers and assistants from OpenAI, Anthropic, Meta, Perplexity, and others," Will Glazier said. "It ignores web pages and requests files that commonly store secrets, including .env configuration files, cloud credential files, private SSH keys, and server environment data, working from a list of roughly 90 file paths. Each address sends a short burst of 50 to 190 requests in about eight seconds and then moves on. The scanner works through targets one at a time, around the clock, and first sends random nonsense paths to find websites that answer every request, a common scanning technique. It hit organizations in financial services, retail, telecommunications, energy, and software, and stayed active from at least late September through late October." China-linked network intrusion The U.S. Embassy in Fiji has revealed that hackers linked to China broke into a regional organization based in Suva between July and August 2026. "Hackers with links to China maintained access to the organization's network over several days," it said. The embassy did not name the threat actor. Nor did it disclose what data the attackers may have accessed. Camera software weaponized Attackers have been breaking into enterprise networks via camera management software, according to new research from security firm Huntress, which observed multiple incidents in September and October 2026 and traced them back to a compromised application. Source code artifacts point to a Korean company selling analog and IP cameras and digital and network video recorders. The activity abuses the legitimate "WpcMon.exe" binary to sideload DLLs that establish outbound connections to a remote server. "This activity demonstrates how attackers can blend malicious code with trusted Windows components to evade detection," Huntress said. 68 GB government data breach In a major operational security blunder, an unknown threat actor stole 68 GB from a Philippine government agency, maintained a detailed log of the transfer, then left that log open on the internet at 13.163.205[.]35:80. "The copy finished in under 24 minutes on September 6, 2026," Hunt.io said. "The transfer log records 27 SQL Server backups whose filenames correspond to the case-management systems of a Philippine overseas-employment and migrant-worker administration. Beside the log sat the operator's toolkit, a rebranded GodPotato build, a PowerShell stager, two payloads and a full Impacket environment." AI model data exfiltration concerns Canadian AI company Cohere has claimed that it caught Alibaba's Qwen3.8-Flash-Next model unsuccessfully attempting to send data to China from its evaluation sandbox as part of a prompt instructing the LLM to detect malicious file download and execution by monitoring for curl processes downloading bash scripts to /tmp followed by bash execution. "Asked to write a defensive detection rule, Qwen3.8-Flash-Next ignored instructions and inventoried the machine it was running on and then tried to upload a probe file to an Alibaba Cloud storage bucket in Beijing," Cohere said. "We cannot answer whether this is deliberate or a leftover glitch from training." Cohere has also released a dataset containing the model trace and corresponding raw token IDs in connection with the behavior. "The exact output is not guaranteed all the time, and many trials may be required to reproduce the behavior," Cohere said, adding "there are similarly unexpected URLs that the model also tends to output, most containing aliyunc." However, the findings have also led to social media chatter that the company is resorting to geopolitical fearmongering and that they are an attempt to clamp down on open-weights models. Post-quantum migration roadmap The U.S. National Institute of Standards and Technology (NIST) has released guidelines that detail the timelines for transitioning away from quantum-vulnerable algorithms to quantum-resistant standards. "The report describes different use cases and says why one migration might take longer than another," said NIST mathematician Dustin Moody, who heads the PQC standardization project. "We understand there's not one strategy that fits all use cases, and we want to help people handle their migration while staying abreast of what's changing." AI-powered ransomware operation exposed SOCRadar has uncovered the live workspace (i.e., open directory) of a threat actor tied to the n0n ransomware group, which exposed the operation's full workflow as of September 2026. The directory at 185.157.161[.]148 includes an AI coding agent configured with about 150 models to produce hundreds of attack scripts, with more than $7,216 in usage costs. "Entry points included a credential stuffing campaign against 305 FortiGate SSL-VPN devices, exposed AWS keys, weak RDP/WinRM credentials, and compromised hosting management portals," SOCRadar said. At least 23 organizations across 14 countries are said to have been identified in the workspace, including a U.S. sports retailer, a cloud provider, a teachers’ union, a Venezuelan ISP, an Argentine ministry and a pharmaceutical subsidiary. Government AI access restricted The Swedish government has barred employees from accessing browser-based versions of ChatGPT or Claude on their work computers over security concerns relating to the processing of sensitive data. "Officials were concerned that entering sensitive information into these models without an agreement setting out how to protect and secure the data could lead to it being fed into the model and stored for training," Euro News reported. 42 repositories hijacked JFrog and SafeDep have uncovered a campaign in which threat actors hijacked third-party 42 GitHub repositories across 11 owners to deploy payload blobs large enough "to evade the GitHub search and API paths normally used to find this kind of compromise." JFrog said, "The repositories contain execution hooks for AI coding assistants and IDEs, plus 12.9 to 13.7 MB polymorphic wrappers that all decode to the same hidden CI-publisher payload." The activity is assessed to be related to a Miasma-family npm worm propagated under various packages ending with "testmetest." According to SafeDep, the worm "shares code with Miasma 'Phantom Gyp' from June 2026 and adds the token-revocation wiper from Mini Shai-Hulud. The malicious versions steal credentials, spread to other packages and repositories, and install a wiper that deletes the home directory when the victim revokes the stolen GitHub token." Unsuspecting developers who installed the packages had their data stolen and repositories compromised with malicious code to produce further malicious testmetest releases and run shellpanel workflows targeting cPanel systems through CVE-2026-41940, overlapping with a prior campaign detailed by Socket in July 2026. Android banking malware-as-a-service A new Android malware operation called MR ROBOT is targeting customers of Indian banks and transforming banking fraud into a subscription business, with cybercriminals renting customized banking trojans to steal OTPs, card details, UPI PINs and credentials while secretly forwarding calls to bypass security checks. "It is not a single-actor campaign but a rented crimeware platform: a master operator leases access to affiliates, who use a Telegram bot ('APK Shield) and a web control panel (v7.0) to build personalized banking trojans on demand and distribute them through fake Play-Store-style pages and messaging-app lures," CloudSEK said. The kit impersonates around 36 lure apps, including banks, utility providers, and government services. One affiliate is estimated to have intercepted 5407 text messages from 153 infected devices. MDM platforms abused for remote access Threat actors are abusing legitimate mobile device management (MDM) platforms, like Hexnode and Rippling, by using social engineering to enroll devices or install management agents, per Huntress. "Once established, MDM provides a trusted, privileged path for malicious activity, such as deploying rogue RMM tools and maintaining remote access," it said. Critical Gotenberg RCE exploited Threat actors are exploiting CVE-2026-42589 (CVSS score: 9.8), a critical remote code execution flaw in Gotenberg, to deliver a Go-based reverse shell called "cache_base." The flaw was patched in May 2026. According to VulnCheck, the activity originated from a residential Japanese IP address in early October 2026. "The execution flow is straightforward: acquire a lock, collect host information, connect to C2, register the victim, and open a shell," VulnCheck said. Over the past 30 days, the vulnerability has recorded 1,358 exploitation events from 128 unique source IP addresses. Discord discussions go public Discord has announced it will allow search engines to index discussions in Discoverable Servers and make them accessible on the web to users outside the platform without an account or invitation, starting mid-December 2026. "Discussions in Discoverable Servers will soon be easier to find when you search the web, so you can find the answer you're looking for and step straight into the conversation on Discord," it said. The changes apply only to Discoverable Servers and do not extend to private servers and direct messages. 800+ ransomware victims claimed The Gentlemen ransomware operation has claimed more than 800 victims across multiple regions and sectors, with most attacks targeting organizations in the U.S. and Europe. "The group supports multiple platforms, with ransomware variants targeting Windows, Linux, NAS, and BSD systems, allowing its affiliates to target a broad range of enterprise environments," Acronis said. "The group's operations include the use of EDR-killing tools. In a recent incident, a custom dropper was observed deploying vulnerable Safetica ProcessMonitorDriver [CVE-2025-70795] and Lenovo BootRepair.sys drivers to terminate security processes." AI model loading RCE risk Pillar Security has disclosed an arbitrary-code-execution vulnerability in Unsloth's core model-loading path (CVE-2026-93348, CVSS score: 8.6). It has been fixed in unsloth_zoo 2026.8.14. "An attacker-controlled model configuration could cause Python code to execute during loading," researcher Ariel Fogel said. "The affected code ran inside the model-loading process, with access to whatever that process could read, modify, or authenticate to. In an AI development environment, that can include proprietary datasets, model artifacts, Hugging Face tokens, and cloud credentials. Exploitation required an affected loading path to process an attacker-controlled configuration." Unauthenticated root-level RCE XBOW said it identified an unauthenticated, critical-severity remote code execution bug in a public web application belonging to the U.S. Election Assistance Commission (EAC). "The vulnerable application was a resource/logistics calculator, not a voting machine or voter registration system," XBOW researcher Ariel Walter Garcia said. "The flaw allowed an unauthenticated attacker to execute code as root inside the backend container, with access to locally protected resources and outbound network connectivity, a privileged foothold reachable via a crafted unauthenticated web request." Session-hijacking RAT emerges A new remote access trojan called DarkCore comes with a dedicated browser that could let attackers access Gmail, WhatsApp, and MediaFire accounts using stolen sessions, while giving the impression that the activity is originating from the victim's own IP address. DarkCore was first advertised on cybercrime forums in August 2026. "The seller describes a browser that reuses those sessions to access work mailboxes, instant messaging apps, cloud storage and other services through the infected machine's IP address," BlackFog said. "The purpose is to make the access look like legitimate activity from the user." AI-powered malware framework Cisco Talos has disclosed details of a new AI-integrated command-and-control (C2) framework called NIK C2. The implant features surveillance, theft, lateral movement, and evasion capabilities, including credential dumping, RDP session hijacking, process hollowing, and a C2-driven screen lock ransomware module. "NIK C2 contains a Windows implant, using which, an actor can dump credentials, stream the victim's keystrokes to collect the targeted victim's sensitive data, and instruct an integrated AI model to analyze the harvested data, all within the compromised session," Talos said. "In this framework, the actor has abused the OpenAI Chat Completions application programming interface (API), which is an HTTP endpoint that enables ChatGPT-style conversations programmatically. In addition to the features that enable theft, an actor can also deploy desktop screen-locking ransomware via the NIK C2 implant onto the victim machine, leading to a ransom demand in Bitcoin or USDT cryptocurrencies." Three different versions of the malware have been identified to date since August 12, 2026. Talos said NIK C2 alters adversary tradecraft by collapsing collection and exploitation into a single continuous session. Malicious PDF delivers backdoor A phishing email using a FedEx tax invoice lure and containing a ZIP archive with a PDF has been observed triggering a multi-stage infection process to deliver a previously undocumented variant of the Sirius Backdoor. "The PDF abuses /OpenAction and /Launch objects to trigger an embedded Base64-encoded PowerShell command upon opening," Trellix said. "Execution relies on social engineering to trick the user into approving the PDF reader's security confirmation prompt. The PowerShell stager decrypts and reflectively loads a .NET assembly in memory. This loader performs process hollowing into legitimate Windows processes such as msbuild.exe, svchost.exe, etc., allowing the malware to operate under trusted process contexts." The final payload is SIRIUS, a Microsoft Visual C++ based backdoor with extended remote access capabilities. AI reshapes ransomware economics A new analysis from Flare has revealed that threat actors are building a mixed AI toolkit, combining commercial models with local, open-weight, and jailbroken alternatives, as well as leaning on stolen AI credentials to shift costs to victims. "Where AI can help is with understanding systems, writing tools and troubleshooting. The threat actor still needs access, decisions and a way to obtain payment," Flare said. "If AI helps an affiliate write a working data-export script without hiring a specialist, the affiliate may avoid that specialist’s fee and the wait for their help. AI makes expertise cheaper to obtain only when the cost of using and checking its work is lower than the cost of the specialist help it replaces." Emerging data-extortion threat A recently observed cyber-extortion actor named ScarlettGroup is publicly advertising alleged data compromises and uses negotiation deadlines and threatened disclosures to pressure targeted organizations. The group's dark web site listing includes victims from technology, education, government, and entertainment sectors. "ScarlettGroup demonstrates characteristics associated with financially motivated data-extortion operations, including public victim claims, deadline-based pressure, and underground forum activity," Foresiet said. "Its dedicated leak-site infrastructure and structured disclosure mechanism indicate an organized approach to promoting alleged compromises and exerting reputational pressure." Infostealers evolve into RATs Following its disruption in June 2026 as part of Operation Endgame, StealC has returned four months later as Stadia. "This time it's not a stealer: it's a full remote access trojan," Varonis said. "The RAT's features include hidden desktop control, a live command shell, a file explorer, a process manager and an in-memory loader, with StealC's stealer welded on as one module among six. The actor behind Stadia is working hard to win back original StealC customers: every former StealC customer is offered a free month on the top ($900) tier." The development comes as Moonlock Lab revealed that the Icarus macOS stealer has similarly evolved from a smash-and-grab crypto and data stealer to a malware with remote-access capabilities. The new iteration is called ICMacOS. "The stealer is actively advertised on cybercrime forums by a Russian-speaking actor operating under the handle GlowComa, with feature updates regularly announced via Telegram," SOCRadar said. "GlowComa promotes ICMacOS alongside Icarus ClickFix, a companion panel designed to deliver payloads using malicious copy-and-paste terminal commands. The infection chain relies on initial dropper scripts to detect the host architecture and harvest administrator passwords using fake system dialogs before delivering the primary payload." Another macOS-focused stealer is Aokigahara, which goes beyond browsers, VPN clients, cryptocurrency wallets, FTP/SFTP clients, password managers, and email applications to also target AI applications and development tools. "The stealer collects authentication files, session data, and configuration files associated with Claude, ChatGPT Desktop, Codex, Cursor, Windsurf, GitHub Copilot, Gemini CLI, and other tools," Check Point said. "Stolen AI credentials could offer opportunities for monetization. Usable credentials or session tokens could enable unauthorized access to paid AI services or the resale of compromised accounts." That's the week's mess. Some attacks were clever, some were painfully simple, and a few attackers made life easier for the people investigating them. The common problem? Too much trust in things nobody was watching closely. AI is adding new tricks, but the old ones aren't going anywhere. Stolen credentials, weak access controls, and forgotten bugs still get plenty of work done. New tools, familiar mistakes. The useful part is knowing where those mistakes keep showing up. That's usually where the next problem starts.
11 shared
Oct 30, 2026
Analyzing Sharepoint Exploits (CVE-2025-53770, CVE-2025-53771), (Wed, Jul 23rd)
On July 19–20, 2025, various security companies and national CERTs published alerts about active exploitation of on-premise SharePoint servers. According to the reports, observed attacks did not require authentication, allowed attackers to gain full control over the infected servers, and were performed using an exploit chain of two vulnerabilities: CVE-2025-49704 and CVE-2025-49706, publicly named “ToolShell”. Additionally, on the same dates, Microsoft released out-of-band security patches for the vulnerabilities CVE-2025-53770 and CVE-2025-53771, aimed at addressing the security bypasses of previously issued fixes for CVE-2025-49704 and CVE-2025-49706. The release of the new, “proper” updates has caused confusion about exactly which vulnerabilities attackers are exploiting and whether they are using zero-day exploits. Kaspersky products proactively detected and blocked malicious activity linked to these attacks, which allowed us to gather statistics about the timeframe and spread of this campaign. Our statistics show that widespread exploitation started on July 18, 2025, and attackers targeted servers across the world in Egypt, Jordan, Russia, Vietnam, and Zambia. Entities across multiple sectors were affected: government, finance, manufacturing, forestry, and agriculture. While analyzing all artifacts related to these attacks, which were detected by our products and public information provided by external researchers, we found a dump of a POST request that was claimed to contain the malicious payload used in these attacks. After performing our own analysis, we were able to confirm that this dump indeed contained the malicious payload detected by our technologies, and that sending this single request to an affected SharePoint installation was enough to execute the malicious payload there. Our analysis of the exploit showed that it did rely on vulnerabilities fixed under CVE-2025-49704 and CVE-2025-49706, but by changing just one byte in the request, we were able to bypass those fixes. In this post, we provide detailed information about CVE-2025-49704, CVE-2025-49706, CVE-2025-53770, CVE-2025-53771, and one related vulnerability. Since the exploit code is already published online, is very easy to use, and poses a significant risk, we encourage all organizations to install the necessary updates. The exploit Our research started with an analysis of a POST request dump associated with this wave of attacks on SharePoint servers. We can see that this POST request targets the “/_layouts/15/ToolPane.aspx” endpoint and embeds two parameters: “MSOtlPn_Uri” and “MSOtlPn_DWP”. Looking at the code of ToolPane.aspx, we can see that this file itself does not contain much functionality and most of its code is located in the ToolPane class of the Microsoft.SharePoint.WebPartPages namespace in Microsoft.SharePoint.dll. Looking at this class reveals the code that works with the two parameters present in the exploit. However, accessing this endpoint under normal conditions is not possible without bypassing authentication on the attacked SharePoint server. This is where the first Microsoft SharePoint Server Spoofing Vulnerability CVE-2025-49706 comes into play. CVE-2025-49706 This vulnerability is present in the method PostAuthenticateRequestHandler, in Microsoft.SharePoint.dll. SharePoint requires Internet Information Services (IIS) to be configured in integrated mode. In this mode, the IIS and ASP.NET authentication stages are unified. As a result, the outcome of IIS authentication is not determined until the PostAuthenticateRequest stage, at which point both the ASP.NET and IIS authentication methods have been completed. Therefore, the PostAuthenticateRequestHandler method utilizes a series of flags to track potential authentication violations. A logic bug in this method enables an authentication bypass if the “Referrer” header of the HTTP request is equal to “/_layouts/SignOut.aspx”, “/_layouts/14/SignOut.aspx”, or “/_layouts/15/SignOut.aspx” using case insensitive comparison. The code displayed in the image above handles the sign-out request and is also triggered when the sign-out page is specified as the referrer. When flag6 is set to false and flag7 is set to true, both conditional branches that could potentially throw an “Unauthorized Access” exception are bypassed. On July 8, 2025, Microsoft released an update that addressed this vulnerability by introducing additional checks to detect the usage of the “ToolPane.aspx” endpoint with the sign-out page specified as the referrer. The added check uses case insensitive comparison to verify if the requested path ends with “ToolPane.aspx”. Is it possible to bypass this check, say, by using a different endpoint? Our testing has shown that this check can be easily bypassed. CVE-2025-53771 We were able to successfully bypass the patch for vulnerability CVE-2025-49706 by adding just one byte to the exploit POST request. All that was required to bypass this patch was to add a “/” (slash) to the end of the requested “ToolPane.aspx” path. On July 20, 2025, Microsoft released an update that fixed this bypass as CVE-2025-53771. This fix replaces the “ToolPane.aspx” check to instead check whether the requested path is in the list of paths allowed for use with the sign-out page specified as the referrer. This allowlist includes the following paths: “/_layouts/15/SignOut.aspx”, “/_layouts/15/1033/initstrings.js”, “/_layouts/15/init.js”, “/_layouts/15/theming.js”, “/ScriptResource.axd”, “/_layouts/15/blank.js”, “/ScriptResource.axd”, “/WebResource.axd”, “/_layouts/15/1033/styles/corev15.css”, “/_layouts/15/1033/styles/error.css”, “/_layouts/15/images/favicon.ico”, “/_layouts/15/1033/strings.js”, “/_layouts/15/core.js”, and it can contain additional paths added by the administrator. While testing the CVE-2025-49706 bypass with the July 8, 2025 updates installed on our SharePoint debugging stand, we noticed some strange behavior. Not only did the bypass of CVE-2025-49706 work, but the entire exploit chain did! But wait! Didn’t the attackers use an additional Microsoft SharePoint Remote Code Execution Vulnerability CVE-2025-49704, which was supposed to be fixed in the same update? To understand why the entire exploit chain worked in our case, let’s take a look at the vulnerability CVE-2025-49704 and how it was fixed. CVE-2025-49704 CVE-2025-49704 is an untrusted data deserialization vulnerability that exists due to improper validation of XML content. Looking at the exploit POST request, we can see that it contains two URL encoded parameters: “MSOtlPn_Uri” and “MSOtlPn_DWP”. We can see how they are handled by examining the code of the method GetPartPreviewAndPropertiesFromMarkup in Microsoft.SharePoint.dll. A quick analysis reveals that “MSOtlPn_Uri” is a page URL that might be pointing to an any file in the CONTROLTEMPLATES folder and the parameter “MSOtlPn_DWP” contains something known as WebPart markup. This markup contains special directives that can be used to execute safe controls on a server and has a format very similar to XML. While this “XML” included in the “MSOtlPn_DWP” parameter does not itself contain a vulnerability, it allows attackers to instantiate the ExcelDataSet control from Microsoft.PerformancePoint.Scorecards.Client.dll with CompressedDataTable property set to malicious payload and trigger its processing using DataTable property getter. Looking at the code of the ExcelDataSet’s DataTable property getter in Microsoft.PerformancePoint.Scorecards.Client.dll, we find the method GetObjectFromCompressedBase64String, responsible for deserialization of CompressedDataTable property contents. The data provided as Base64 string is decoded, unzipped, and passed to the BinarySerialization.Deserialize method from Microsoft.SharePoint.dll. Attackers use this method to provide a malicious DataSet whose deserialized content is shown in the image above. It contains an XML with an element of dangerous type "System.Collections.Generic.List1[[System.Data.Services.Internal.ExpandedWrapper2[...], System.Data.Services, Version=4.0.0.0, Culture=neutral, PublicKeyToken=b77a5c561934e089]]", which allows attackers to execute arbitrary methods with the help of the well-known ExpandedWrapper technique aimed at exploitation of unsafe XML deserialization in applications based on the .NET framework. In fact, this shouldn’t be possible, since BinarySerialization.Deserialize in Microsoft.SharePoint.dll uses a special XmlValidator designed to protect against this technique by checking the types of all elements present in the provided XML and ensuring that they are on the list of allowed types. However, the exploit bypasses this check by placing the ExpandedWrapper object into the list. Now, to find out why the exploit worked on our SharePoint debugging stand with the July 8, 2025 updates installed, let’s take a look at how this vulnerability was fixed. In this patch, Microsoft did not really fix the vulnerability but only mitigated it by adding the new AddExcelDataSetToSafeControls class to the Microsoft.SharePoint.Upgrade namespace. This class contains new code that modifies the web.config file and marks the Microsoft.PerformancePoint.Scorecards.ExcelDataSet control as unsafe. Because SharePoint does not execute this code on its own after installing updates, the only way to achieve the security effect was to manually run a configuration upgrade using the SharePoint Products Configuration Wizard tool. Notably, the security guidance for CVE-2025-49704 does not mention the need for this step, which means at least some SharePoint administrators may skip it. Meanwhile, anyone who installed this update but did not manually perform a configuration upgrade remained vulnerable. CVE-2025-53770 On July 20, 2025, Microsoft released an update with a proper fix for the CVE-2025-49704 vulnerability. This patch introduces an updated XmlValidator that now properly validates element types in XML, preventing exploitation of this vulnerability without requiring a configuration upgrade and, more importantly, addressing the root cause and preventing exploitation of the same vulnerability through controls other than Microsoft.PerformancePoint.Scorecards.ExcelDataSet. CVE-2020-1147 Readers familiar with previous SharePoint exploits might feel that the vulnerability CVE-2025-49704/CVE-2025-53770 and the exploit used by the attackers looks very familiar and very similar to the older .NET Framework, SharePoint Server, and Visual Studio Remote Code Execution Vulnerability CVE-2020-1147. In fact, if we compare the exploit for CVE-2020-1147 and an exploit for CVE-2025-49704/CVE-2025-53770, we can see that they are almost identical. The only difference is that in the exploit for CVE-2025-49704/CVE-2025-53770, the dangerous ExpandedWrapper object is placed in the list. This makes CVE-2025-53770 an updated fix for CVE-2020-1147. Conclusions Despite the fact that patches for the ToolShell vulnerabilities are now available for deployment, we assess that this chain of exploits will continue being used by attackers for a long time. We have been observing the same situation with other notorious vulnerabilities, such as ProxyLogon, PrintNightmare, or EternalBlue. While they have been known for years, many threat actors still continue leveraging them in their attacks to compromise unpatched systems. We expect the ToolShell vulnerabilities to follow the same fate, as they can be exploited with extremely low effort and allow full control over the vulnerable server. To stay better protected against threats like ToolShell, we as a community should learn lessons from previous events in the industry related to critical vulnerabilities. Specifically, the speed of applying security patches nowadays is the most important factor when it comes to fighting such vulnerabilities. Since public exploits for these dangerous vulnerabilities appear very soon after vulnerability announcements, it is paramount to install patches as soon as possible, as a gap of even a few hours can make a critical difference. At the same time, it is important to protect enterprise networks against zero-day exploits, which can be leveraged when there is no available public patch for vulnerabilities. In this regard, it is critical to equip machines with reliable cybersecurity solutions that have proven effective in combatting ToolShell attacks before they were publicly disclosed. Kaspersky Next with its Behaviour detection component proactively protects against exploitation of these vulnerabilities. Additionally, it is able to detect exploitation and the subsequent malicious activity. Kaspersky products detect the exploits and malware used in these attacks with the following verdicts: UDS:DangerousObject.Multi.Generic PDM:Exploit.Win32.Generic PDM:Trojan.Win32.Generic HEUR:Trojan.MSIL.Agent.gen ASP.Agent.* PowerShell.Agent.*
10 shared
Jul 28, 2025
Microsoft releases emergency .NET patches for critical Brotli flaw
A vulnerability in Google’s Brotli data compression library, tracked as CVE-2026-111497 and dubbed Node2Shell, has led to security updates from Microsoft, the Node.js project and the maintainers of two Python packages. Node.js and the Python packages were patched last week, and Microsoft followed on October 25 with fixes for .NET, Visual Studio and PowerShell. Bun, Envoy and Istio have also been updated. Brotli is a popular choice for compressing data sent over the web, and its decoder is embedded in a long list of applications and libraries. Described as an out-of-bounds write, the bug impacts Brotli 1.0.3 through 1.2.0. Google gave it a CVSS v4 score of 9.2, which puts it in the critical category. Brotli versions 1.0.10, 1.1.1 and 1.2.1 contain the fix. The Node.js project said specially crafted input can push data beyond the limits of a buffer used by the decoder. The resulting memory corruption could cause the process to crash or leak memory contents, and could also allow an unauthenticated attacker to run arbitrary code. Node.js credited the discovery to members of OpenAI Codex Security. According to OpenAI, the issue was uncovered during red-teaming work, after which the company notified the Brotli developers and the projects that rely on the library. OpenAI noted that the fix predates the disclosure. “This root cause issue was actually fixed in the Brotli source code in February, but it wasn’t known at the time that it gave rise to a security vulnerability and there was no more recent release of Brotli,” the AI company said. Code execution demonstrated on official Node.js image Imperva has shown that it can be exploited for code execution on the official Node.js 24.22.0 image for Linux arm64. Its researchers sent the malicious data both in a server response retrieved by the targeted application and in a request body processed by Express 5 or body-parser 2. “The proof did not succeed on every attempt. Our results establish code execution for the tested Linux arm64 build and application setups, and show how the fixed build handled the same inputs,” Imperva said. The security firm has not made its exploit public. Attacks only work if malicious Brotli data reaches the decoder, for instance through a library that unpacks compressed content on the application’s behalf. “Any application that passes attacker-controlled data to an affected Google Brotli decoder may be exposed. This includes compressed HTTP request bodies, responses fetched from untrusted servers, and compressed files,” OpenAI’s Patch the Planet initiative said in its advisory. No exploitation in the wild has been reported so far. A proof-of-concept exploit published on GitHub reportedly achieves code execution only against an intentionally weakened build, and some researchers argued the bug can only be used for denial-of-service (DoS) attacks. Microsoft products and Python packages affected Microsoft’s October 25 updates include .NET runtime versions 8.0.33, 9.0.22 and 10.0.14, along with .NET 11 Release Candidate 3. Visual Studio 2019, 2022 and 2026, as well as PowerShell 7.4, 7.5 and 7.6, have also been updated. Microsoft has categorized CVE-2026-111497 as an elevation of privilege issue with a CVSS v3.1 base score of 8.1. It rates the flaw critical for .NET and Visual Studio and important for PowerShell, and its exploitability assessment is “Exploitation More Likely.” In Python’s case, the vulnerable decoder is built into two PyPI packages, Brotli and brotlicffi. They have been patched with the release of versions 1.2.1 and 1.2.1.0, respectively. As more affected software emerged, researchers began referring to the flaw as HTTP2Shell and Broccoli2Shell. A public tracker of software that bundles its own copy of the Brotli decoder lists several projects that are still unpatched, including DuckDB, Apache Arrow, 7-Zip-zstd, p7zip and EDK II. Its maintainers say the list is incomplete, and that not every configuration of these projects necessarily exposes the vulnerable code. Applying the updates also requires restarting affected services and rebuilding container images on top of a patched base, since processes that are already running keep using the vulnerable code. Related: Mirai Botnet Operators Join PHP2Shell Attacks as ASLR Bypass Exploits Emerge Related: Attackers Exploit Third Arista VCO Zero-Day in Four Months Related: LiteLLM Compromised in Fresh Supply Chain Attack
10 shared
Oct 29, 2026