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Qilin Ransomware Group Publishes Over 40 Cases Monthly

A surge in Qilin ransomware activity has continued through the second half of 2025, with the group publishing more than 40 victim listings per month on its leak site. The attacks have primarily targeted the manufacturing sector, followed by professional and scientific services and wholesale trade, according to new findings from Cisco Talos. The sustained rate of publication underscores Qilin’s position as one of the most active and damaging ransomware operations worldwide. Using a double-extortion model, the group encrypts data while threatening to leak stolen information if ransoms are not paid. A Growing Global Footprint Since emerging in mid-2022, Qilin, formerly known as Agenda, has expanded its reach through a ransomware-as-a-service (RaaS) model. Affiliates use Qilin’s platform and…

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Qilin ransomware abuses WSL to run Linux encryptors in Windows
The Qilin ransomware operation was spotted executing Linux encryptors in Windows using Windows Subsystem for Linux (WSL) to evade detection by traditional security tools. The ransomware first launched as "Agenda" in August 2022, rebranding to Qilin by September and continuing to operate under that name to this day. Qilin has become one of the most active ransomware operations, with new research from Trend Micro and Cisco Talos stating that the cybercrime gang has attacked more than 700 victims across 62 countries this year. Both firms say the group has become one of the most active ransomware threats worldwide, publishing over 40 new victims per month in the second half of 2025. Both cybersecurity firms report that Qilin affiliates use a mix of legitimate programs and remote management tools to breach networks and steal credentials, including applications such as AnyDesk, ScreenConnect, and Splashtop for remote access, and Cyberduck and WinRAR for data theft. The threat actors also use common built-in Windows utilities, such as Microsoft Paint (mspaint.exe) and Notepad (notepad.exe), to inspect documents for sensitive data before stealing them. Using vulnerable drivers to disable security tools Both Trend Micro and Talos also observed Qilin affiliates performing Bring Your Own Vulnerable Driver (BYOVD) attacks to disable security software before launching encryptors. The attackers deployed signed but vulnerable drivers, such as eskle.sys, to terminate antivirus and EDR processes, and used DLL sideloading to drop additional kernel drivers (rwdrv.sys and hlpdrv.sys) that granted further kernel-level privileges. Talos observed the attackers using tools such as "dark-kill" and "HRSword" to turn off security software and remove traces of malicious activity. "Talos observed traces of attempts to disable EDR using multiple methods," explained Cisco Talos. "Broadly speaking, we have frequently observed commands that directly execute the EDR's 'uninstall.exe' or attempt to stop services using the sc command. At the same time, attackers have also been observed running open-source tools such as dark-kill and HRSword." Linux encryptor launched via WSL In December 2023, BleepingComputer reported on a new Qilin Linux encryptor with a strong focus on encrypting VMware ESXi virtual machines and servers. The encryptor's command-line arguments include options to enable debug mode, perform a dry run without encrypting any files, or customize how virtual machines and their snapshots are encrypted. Researchers from Trend Micro now report that Qilin affiliates have been seen using WinSCP to transfer the Linux ELF encryptor to compromised devices, which is then launched through the Splashtop remote management software (SRManager.exe) directly within Windows. While Trend Micro initially reported the encryptor as cross-platform, Qilin’s Linux encryptors are ELF executables [VirusTotal], meaning they cannot run natively on Windows and require a runtime environment such as the Windows Subsystem for Linux (WSL) to execute. Further questions to Trend Micro revealed that the threat actors are indeed utilizing the WSL to execute the encryptor. WSL is a Windows feature that allows you to install and run Linux distributions directly within Windows. Once installed, you can either open a shell for the default, installed distro or use the wsl.exe -e command to run Linux programs within a Windows command prompt. Trend Micro told BleepingComputer that when threat actors gain access to a device, they enable or install the Windows Subsystem for Linux and then use it to execute the encryptor, thereby evading traditional Windows security software. "In this case, the threat actors were able to run the Linux encryptor on Windows systems by taking advantage of the Windows Subsystem for Linux (WSL), a built-in feature that allows Linux binaries to execute natively on Windows without requiring a virtual machine," Trend Micro told BleepingComputer. "After gaining access, the attackers enabled or installed WSL using scripts or command-line tools, then deployed the Linux ransomware payload within that environment. This gave them the ability to execute a Linux-based encryptor directly on a Windows host while avoiding many defenses that are focused on detecting traditional Windows malware." As many Windows EDR products focus on Windows PE behavior, they miss malicious behavior occurring within WSL, allowing malware to bypass detection. Trend Micro says the technique shows how ransomware operators are adapting to hybrid Windows and Linux environments to maximize reach and evade traditional defenses. 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.comOct 28, 2025extracted
Researchers warn of Qilin ransomware gang after group hit hundreds of orgs this year
Researchers warn of Qilin ransomware gang after group hit hundreds of orgs this year The Qilin ransomware gang has emerged as one of the most active cybercriminal operations in 2025, listing hundreds of victims throughout the year that include large companies, local governments and hospitals. In October alone, the suspected Russia-based group added more than 185 victims to its leak site — claiming to be behind recent cybersecurity incidents at Japanese beverage giant Asahi, the Texas city of Sugar Land, a county government in North Carolina and multiple power companies in Texas. Incident responders at cybersecurity firm Cisco Talos published a study of the group this weekend, warning that in the second half of 2025, Qilin has published the information of about 40 victims per month. The group has existed since July 2022 but expanded its operations in the last few years, now operating through the ransomware-as-a-service (RaaS) business model. Nearly a quarter of the group’s attacks impact the manufacturing sector, with another 18% of attacks hitting the professional and scientific services industry and 10% of attacks targeting wholesale trade firms. Cisco Talos said it has responded to multiple incidents involving Qilin but is unable to identify a singular intrusion technique used in each attack. In many cases, the attackers used stolen administrative credentials found on the dark web — allowing them to access VPNs. Cybersecurity research firm Comparitech tracked more than 700 Qilin attacks in 2025, with 118 being confirmed. About half of the attacks targeted the U.S., while France, Canada, South Korea and Spain also had a large proportion of organizations that dealt with Qilin incidents. Rebecca Moody, head of data research at Comparitech, said the shift to operating as a RaaS group has allowed Qilin to scale up rapidly and target more organizations with a higher level of success. The group has also upped its ransom demands this year. Malaysian officials were outraged in March, with the country’s Prime Minister telling the press that it rejected a $10 million ransom demand after Kuala Lumpur International Airport was attacked. One month earlier, the group demanded $4 million after shutting down Cleveland’s Municipal Court. The group faced law enforcement scrutiny last year after a devastating attack on a British healthcare company that prompted major disruptions to services. But it quickly returned with attacks on the government of Palau and one of the largest newspaper chains in the United States. Jonathan Greig is a Breaking News Reporter at Recorded Future News. Jonathan has worked across the globe as a journalist since 2014. Before moving back to New York City, he worked for news outlets in South Africa, Jordan and Cambodia. He previously covered cybersecurity at ZDNet and TechRepublic.
therecord.mediaOct 28, 2025extracted
Qilin Ransomware Group Publishes Over 40 Cases Monthly
A surge in Qilin ransomware activity has continued through the second half of 2025, with the group publishing more than 40 victim listings per month on its leak site. The attacks have primarily targeted the manufacturing sector, followed by professional and scientific services and wholesale trade, according to new findings from Cisco Talos. The sustained rate of publication underscores Qilin’s position as one of the most active and damaging ransomware operations worldwide. Using a double-extortion model, the group encrypts data while threatening to leak stolen information if ransoms are not paid. A Growing Global Footprint Since emerging in mid-2022, Qilin, formerly known as Agenda, has expanded its reach through a ransomware-as-a-service (RaaS) model. Affiliates use Qilin’s platform and tools to compromise organizations across the United States, Canada, the United Kingdom, France and Germany. Talos observed a sharp rise in data leaks, with peaks of 100 victim postings in both June and August 2025. Recent artifacts suggest that some of the attacker’s scripts used Cyrillic character encoding, possibly linking the operation to Eastern Europe or a Russian-speaking region. Qilin Tools and Tactics In its latest report, Talos identified the use of the open-source file transfer tool Cyberduck for data exfiltration, leveraging trusted cloud services to conceal malicious traffic. Investigators also noted unusual activity involving standard Windows programs such as notepad.exe and mspaint.exe, which were used to view sensitive files before exfiltration. Qilin operators commonly deploy two encryptors during an attack, one spreading laterally across systems via PsExec and another running from a single host to encrypt multiple network shares. The report highlights several additional tactics: Abuse of leaked administrative credentials to access VPNs without multi-factor authentication (MFA) Credential theft using Mimikatz and NirSoft utilities Obfuscated PowerShell scripts disabling Windows security features Attempts to uninstall or stop endpoint detection and response (EDR) tools Persistent and Damaging Attacks Talos found that Qilin often uses scheduled tasks and registry modifications to maintain persistence after encryption. The ransomware replaces victims’ wallpapers with ransom notices linking to a Tor-based leak site and a backup URL for victims without Tor access. Manufacturing accounted for roughly 23% of all incidents, while professional and scientific services represented about 18% and wholesale trade around 10%. Despite fluctuations in monthly figures, analysts warn that Qilin continues to pose a major threat, particularly given its operational consistency and expanding affiliate base.
infosecurity-magazine.comOct 27, 2025extracted
Qilin Ransomware Combines Linux Payload With BYOVD Exploit in Hybrid Attack
The ransomware group known as Qilin (aka Agenda, Gold Feather, and Water Galura) has claimed more than 40 victims every month since the start of 2025, barring January, with the number of postings on its data leak site touching a high of 100 cases in June. The development comes as the ransomware-as-a-service (RaaS) operation has emerged as one of the most active ransomware groups, accounting for 84 victims each in the months of August and September 2025. The Russian-speaking threat group emerged around July 2022. According to data compiled by Cisco Talos, the U.S., Canada, the U.K., France, and Germany are some of the countries most impacted by Qilin. The attacks have primarily singled out manufacturing (23%), professional and scientific services (18%), and wholesale trade (10%) sectors. Attacks mounted by Qilin affiliates have likely leveraged leaked administrative credentials on the dark web for initial access using a VPN interface, followed by performing RDP connections to the domain controller and the successfully breached endpoint. In the next phase, the attackers conducted system reconnaissance and network discovery actions to map the infrastructure, and executed tools like Mimikatz, WebBrowserPassView.exe, BypassCredGuard.exe, and SharpDecryptPwd to facilitate credential harvesting from various applications and exfiltrate the data to an external SMTP server using a Visual Basic Script. "Commands executed via Mimikatz targeted a range of sensitive data and system functions, including clearing Windows event logs, enabling SeDebugPrivilege, extracting saved passwords from Chrome's SQLite database, recovering credentials from previous logons, and harvesting credentials and configuration data related to RDP, SSH, and Citrix," Talos said. Further analysis has uncovered the threat actor's use of mspaint.exe, notepad.exe, and iexplore.exe to inspect files for sensitive information, as well as a legitimate tool called Cyberduck to transfer files of interest to a remote server, while obscuring the malicious activity. The stolen credentials have been found to enable privilege escalation and lateral movement, with the actors abusing the elevated access to install multiple Remote Monitoring and Management (RMM) tools like AnyDesk, Chrome Remote Desktop, Distant Desktop, GoToDesk, QuickAssist, and ScreenConnect. Talos said it could not definitively conclude if the programs were used for lateral movement. To sidestep detection, the attack chain involves the execution of PowerShell commands to disable AMSI, turn off TLS certificate validation, and enable Restricted Admin, in addition to running tools such as dark-kill and HRSword to terminate security software. Also deployed on the host are Cobalt Strike and SystemBC for persistent remote access. The infection culminates with the launch of the Qilin ransomware, which encrypts files and drops a ransom note in each encrypted folder, but not before wiping event logs and deleting all shadow copies maintained by the Windows Volume Shadow Copy Service (VSS). The findings coincide with the discovery of a sophisticated Qilin attack that deployed their Linux ransomware variant on Windows systems and combined it with legitimate IT tools and the bring your own vulnerable driver (BYOVD) technique to bypass security barriers. "The attackers abused legitimate tools, specifically installing AnyDesk through Atera Networks' remote monitoring and management (RMM) platform and ScreenConnect for command execution. It abuses Splashtop for the final ransomware execution," Trend Micro said. "They specifically targeted Veeam backup infrastructure using specialized credential extraction tools, systematically harvesting credentials from multiple backup databases to compromise the organization's disaster recovery capabilities before deploying the ransomware payload." Besides using valid accounts to breach target networks, select attacks have employed spear-phishing and ClickFix-style fake CAPTCHA pages hosted on Cloudflare R2 infrastructure to trigger the execution of malicious payloads. It's assessed that these pages deliver the information stealers necessary to harvest credentials that are then used to obtain initial access. Some of the crucial steps taken by the attackers are as follows - Deploying a SOCKS proxy DLL to facilitate remote access and command execution Abusing ScreenConnect's remote management capabilities to execute discovery commands and running network scanning tools to identify potential lateral movement targets Targeting the Veeam backup infrastructure to harvest credentials Using the "eskle.sys" driver as part of a BYOVD attack to disable security solutions, terminate processes, and evade detection Deploying PuTTY SSH clients to facilitate lateral movement to Linux systems Using SOCKS proxy instances across various system directories to obfuscate command-and-control (C2) traffic by means of the COROXY backdoor Using WinSCP for secure file transfer of the Linux ransomware binary to the Windows system Using Splashtop Remote's management service (SRManager.exe) to execute the Linux ransomware binary directly on Windows systems "The Linux ransomware binary provided cross-platform capability, allowing the attackers to impact both Windows and Linux systems within the environment using a single payload," Trend Micro researchers noted. "Updated samples incorporated Nutanix AHV detection, expanding targeting to include hyperconverged infrastructure platforms. This demonstrated the threat actors' adaptation to modern enterprise virtualization environments beyond traditional VMware deployments."
thehackernews.comOct 27, 2025extracted
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Check Point, Kaspersky, Tanium Patch Product Vulnerabilities
Attackers exploited a previously unknown flaw in Check Point's Security Management Server in a handful of targeted attacks on July 23, the company said. The flaw, CVE-2026-93616, allows an attacker who can access the server's web service to run scripts on it without logging in. Check Point released a fix on September 22 for the server that controls firewall policies for the Check Point gateways it manages. Separately, Check Point said attackers have been trying since September 12 to exploit a VPN flaw it fixed on September 9. The attempts, against a flaw tracked as CVE-2026-85102, have targeted customers of Spark, Check Point's firewall line for small businesses. When the fix came out, Check Point had no evidence the flaw was being exploited. CVE-2026-93616 is a path traversal bug in the management server's web service. The service does not properly limit which files and folders a request can reach. An attacker can use it to upload scripts to the server and then run them. Check Point rated it 9.8 out of 10 on the CVSS scale in the CVE record for the flaw. Check Point's advisory does not name the targets of the July attacks or the attackers, nor does it say what the attackers did after exploiting the flaw. Management Server Versions and Fix Check Point numbers the Jumbo Hotfix updates for each release by "Take." Its LivePatch channel, which pushes urgent fixes, uses a separate set of take numbers. The CVE record lists these versions as affected: R82.20 with no Jumbo Hotfix installed R82.10 with Jumbo Hotfix Take 44 or below R82 with Jumbo Hotfix Take 126 or below R81.20 with Jumbo Hotfix Take 166 or below R81.10 with Jumbo Hotfix Take 190 or below (end of support) R81, R80.40, R80.30, R80.20, R80.10 and R80 (all end of support) Check Point's advisory lists R82.20 as affected without the "no Jumbo Hotfix" condition. On September 16, Check Point fixed a separate flaw in the management server, CVE-2026-91843, through LivePatch. That update was LivePatch Take 28, or Take 29 on R82.20, according to a summary of Check Point's advisory by France's CERT Santé. Check Point says those LivePatch takes do not fix CVE-2026-93616. CVE-2026-85103, a VPN certificate flaw that Check Point fixed on September 9, affected both gateways and management servers. On R82.10, R82, and R81.20, the new flaw's affected list goes one take higher than that flaw's. So a server updated only enough to be outside that September flaw's range is still affected by CVE-2026-93616. The fixed builds, and Check Point's guidance on mitigation, hunting and indicators of compromise, are in support article sk1000171. Administrators of management servers should: Check the server's release and Jumbo Hotfix take against the list above. Install the fix listed in sk1000171. Use the hunting guidance and indicators of compromise in sk1000171 to look for signs of an attack. Installing the fix does not show whether the server was attacked before. Check Point's advisory names only Security Management as affected and does not say what network access an attacker needs. The Hacker News has asked Check Point about other affected products, the fixed builds, and the July attacks. Spark Firewalls Targeted Through VPN Flaw CVE-2026-85102 is in the way Check Point gateways check certificates while a VPN connection is being set up. It may let an attacker who has not logged in run code on the gateway. Fixes have been out since September 9 and are in support article sk1000117. The affected products are Security Gateway and Spark firewalls, whether centrally or locally managed, on R81 and R81.10 (both end of support), R81.10.x, R81.20, R82, R82.00.x and R82.10. The Netherlands' National Cyber Security Centre (NCSC) says the flaw applies when these products use Site-to-Site VPN or Remote Access VPN. Check Point said the attempts came from anonymizing infrastructure, including VPN services and proxies, and used certificates with these subjects: Certificate subject: CN=vpn,OU=users,O=global Certificate subject: CN=vpn-user,OU=users,O=global Certificate subject: CN=vpnuser,OU=users,O=global The list is not complete, and other subjects may be in use. Administrators should check logs for any unusual certificate-based Mobile Access login, not only those with these subjects. They should also check what suspicious Mobile Access users do after logging in, which often includes scanning internal ports and services. Check Point says customers who installed the September 9 fix are protected, but its advisory does not say whether any attempt succeeded. For gateways that cannot be patched yet, the NCSC lists a Check Point workaround for Site-to-Site VPN: turn off the implied VPN rules and allow UDP ports 500 and 4500 only from specific peer IP addresses. The workaround does not apply to locally managed Spark firewalls. Mitigation steps from Check Point are in sk1000117.
7 shared
Sep 23, 2026
2026-013: Critical Vulnerability in F5 BIG-IP APM
History: 22/09/2026 --- v1.0 -- Initial publication Summary On 22 September 2026, F5 published an advisory addressing a critical vulnerability affecting its BIG-IP APM product. The vendor confirmed active exploitation in the wild [1]. CERT-EU recommends taking appropriate actions as soon as possible. Technical Details The vulnerability CVE-2026-94127, with a CVSS score of 9.8, is a heap-based buffer overflow vulnerability and allow unauthenticated attacker to achieve remote code execution (RCE) on the affected device [1]. Affected Products The vulnerability affects the following versions of BIG-IP APM if configured with an access policy and an OAuth profile on a virtual server [1]: 17.1.0 - 17.1.3 17.5.0 - 17.5.1 21.1.0 Recommendations CERT-EU recommends taking the following actions as soon as possible: Preserve forensic evidence. Apply the relevant hotfix. Check for signs of compromise (see the compromise assessment section). If any sign of compromise is detected, start the incident response process. Mitigation If patching cannot be applied immediately, F5 provides an iRule-based mitigation for the affected virtual server. To obtain it, F5 BIG-IP clients should contact the F5 support [1]. Compromise Assessment CERT-EU strongly advises to look for the following indicators of compromise provided by the vendor in its advisory [1]: At a high level, multiple OAuth authentication failures, followed by suspicious commands, shortly followed by a TMM SIGABRT is the combination that should lead to human review of the system. OAuth authentication failures: check /var/log/apm for repeated occurrences of the following, especially 10 or more from a single IP in a short window. err tmm1\[30975\]: 01990004:3: : Request UserInfo from Source ID (null) IP failed. Error Code (invalid\_token) Error Description (The access token is invalid.) - Increase of OAuth failure statistics. Run the following and look for an unexplained increase in total_failed : $ tmctl global_oauth_stat -s total_requests,total_userinfo_requests,total_failed - Audit log anomalies: if OAuth failures are observed, review /var/log/audit around those timestamps for suspicious commands. TMM core files: Presence of a TMM core file alone is not an indicator, but core files should be investigated. The vendor indicates that they have observed TMM entering a loop, which causes the SOD daemon to send a SIGABRT.
7 shared
Sep 25, 2026
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.
6 shared
Aug 1, 2025
Cisco patches actively exploited email gateway zero-day (CVE-2026-76461)
Criminals are exploiting a critical Cisco Secure Email Gateway flaw that can turn a malicious email into root access. The vulnerability, tracked as CVE-2026-76461, carries a 9.8 CVSS score and affects physical and virtual Secure Email Gateway appliances regardless of their configuration. Cisco says there are no workarounds, so patching is the only fix. The bug lies in how Cisco's AsyncOS software handles incoming email. An attacker doesn't need to log in: they can send a booby-trapped message through a vulnerable gateway and, if the exploit works, run commands as root. Which is not exactly what you want from the box tasked with keeping nasty emails out. Cisco's Product Security Incident Response Team said it became aware of active exploitation in September, although the networking giant hasn't said who is behind the attacks, how long they have been going on, or how many organizations have been compromised. Cisco uncovered the bug while resolving a Technical Assistance Center support case. Signs suggest at least some Cisco cloud customers were caught up in the attacks. Cisco said it investigated devices belonging to its Secure Email Cloud service and directly contacted customers whose appliances showed indicators of possible compromise. It is now carrying out remediation and recovery work and says all of its Secure Email Cloud devices have been upgraded to AsyncOS 16.5.0-780. Admins running their own appliances have a little more work to do. Cisco recommends checking logs for signs of suspicious activity, but warns that finding nothing doesn't necessarily mean the system is clean. Once attackers have root access, Cisco says they could tamper with the logs and cover their tracks. Admins are also being told to check network and firewall logs for anything unusual, rather than relying on the gateway itself for answers. For virtual appliances suspected of being compromised, Cisco's recovery advice is fairly drastic: preserve the forensic evidence, deploy a fresh VM running fixed software, rebuild the configuration, and rotate credentials and cryptographic material. Cisco has fixed the bug in AsyncOS releases 15.5.5-014, 16.0.4-302 and 16.5.0-780, with customers strongly encouraged to move to the latter. There's still a decent-sized target pool out there. The Shadowserver Foundation was tracking more than 400 Cisco Secure Email Gateway appliances exposed to the internet as of Monday The flaw has also landed in CISA's Known Exploited Vulnerabilities catalog, with US federal civilian agencies ordered to remediate it by September 17. CVE-2026-76461 comes less than a year after attackers exploited another critical AsyncOS flaw, CVE-2025-20393, to break into Cisco Secure Email Gateway appliances and install persistence mechanisms. That bug eventually scored a perfect 10. For anyone still running an affected gateway, the message is fairly simple: the box designed to inspect hostile email can itself be pwned by one; attackers are already doing it, and there is no workaround to hide behind. ®
6 shared
Sep 18, 2026
Hackers exploit Sangoma Switchvox flaw to deploy reverse shells
Malware linked to break-ins at F5 BIG-IP Access Policy Manager appliances hides a PHP web shell in memory instead of in a file on disk, Sophos said in an analysis published on September 7. When Apache loads any of the three appliances' own PHP scripts, the malware adds the web shell to the copy held in memory, so a check of the file on disk can come back clean. Those three scripts are the same ones F5 pointed customers to in March, when it said changes to them alone do not show a break-in. A web shell is usually a small script an attacker drops into a web server's folders to run commands through ordinary web requests. Because it sits on disk, defenders look for it by scanning files and comparing them against known-good copies. That approach does not work here. As the researchers put it, the web shell "does not need to exist in its final form on disk." The three scripts are apm_css.php3, full_wt.php3 and webtop_popup_css.php3, part of the BIG-IP APM webtop. F5 named all three in March in a published list of indicators of compromise for the malware it tracks as c05d5254, and said at the time that their presence alone does not point to a security problem. F5 also said it had seen cases where a web shell was written to disk, but that the web shells "have been observed to work in memory only," which means the files it listed might not be modified. The Sophos analysis explains how both statements can be true at once. Sophos examined a single sample. Its analysis names no victim and does not say how the sample was obtained. F5 has linked the c05d5254 activity to appliances affected by CVE-2025-53521, Sophos said. F5 first published that flaw on October 15, 2025, as a denial-of-service problem. On March 27, 2026, F5 said new information had led it to reclassify the flaw as remote code execution, and that it had been exploited. An attacker needs no login to use it, and F5 rates it 9.8 on CVSS 3.1 and 9.3 on CVSS 4.0. CISA added it to its Known Exploited Vulnerabilities catalog the same day, giving U.S. federal civilian agencies until March 30 to act. The flaw applies where a BIG-IP APM access policy is set on a virtual server. The UK's National Cyber Security Center calls BIG-IP APM a common component, especially in large organizations. F5's advisory lists the affected and fixed releases. The patch that fixes this is nearly a year old. Ireland's National Cyber Security Center said in a March 31 advisory that the patch released in October is still valid and will protect against exploitation. The web shell is the last step in a longer chain, and the earlier steps do touch the disk. Sophos said a separate installer, found in a sample named umount, infects the Apache web server program at /usr/sbin/httpd by adding malicious code to the front of the real file. The size of that added code matches the payload carried inside the installer, which Sophos said strongly suggests the installer puts it there. ESET, which analyzed related samples in April and named the malware PoisonedRefresh, said the installer is meant to be run as root and turns off SELinux. It also infects umount, httpd and rc.local inside BIG-IP install images, which ESET said was presumably done to spread the malware to other systems through the installation media. Because the malware sits inside the Apache program, it runs before Apache's own code starts. Sophos said it hooks an Apache Portable Runtime function, apr_dso_load, and does nothing until Apache loads the PHP module, libphp. Once PHP is loaded, the malware reads /proc/self/maps to find the module in memory, briefly makes those memory pages writable, rewrites the calls the module uses to open, size, and map files, then puts the original permissions back. From that point, it controls what PHP sees when it opens one of the three scripts. When the file is mapped into memory, the malware places the web shell in front of the original content. The web shell reads the raw body of a request, checks it for a short marker, decrypts the rest, and runs it. It replies with HTTP status 201 and a CSS content type, so the exchange looks like a request for a stylesheet. The malware also opens a local socket at /run/bigtlog.pipe. After checking for a fixed token, it connects that socket to /bin/bash, giving an interactive shell without opening a network port. Sophos said it could not find any code in the sample for connecting to that socket, and no other use of the token, so the two ways in look like separate features. It has no evidence either way on whether the attacker reaches the socket through the web shell. What Defenders Can Check Sophos said its behavioral signals are leads to investigate, not proof on their own, and should be read alongside file, process, and memory evidence. The list below combines them with the indicators F5 published in March. File: /run/bigtlog.pipe or /run/bigstart.ltm present Binary: hash, size or timestamp mismatch on /usr/bin/umount or /usr/sbin/httpd against a known good copy. F5 notes that sizes and timestamps differ between releases and engineering hotfixes Tool: sys-eicheck failing because one of those two files has changed Log: an entry in /var/log/restjavad-audit showing a local user reaching the iControl REST API from localhost Log: an entry in /var/log/auditd showing SELinux being switched off by the same route Log: an entry in /var/log/audit showing a bash command run through iControl REST. F5 says these lines show base64 data written into a file and /run/bigstart.ltm being run Traffic: HTTP 201 responses carrying a CSS content type from the appliance Host behavior: an Apache worker reading /proc/self/maps, changing memory permissions around libphp, binding a socket under /run, or starting /bin/bash SHA-256: 26bd5b0722d1dbab5db749a063c49bc8638653ac2addfead7a9cb3d6d57bccc9 File, weak on its own: changes to the three .php3 scripts. F5 says their presence alone does not show a problem, and the Sophos analysis explains why: the file does not have to change at all F5's list also includes items the Sophos analysis does not cover, among them /run/bigstart.ltm and the changes affecting sys-eicheck. Neither account describes the whole intrusion. If You Have Already Patched Patching does not settle whether an appliance was compromised before the patch went on. Ireland's NCSC said no timeline for exploitation is available, and that it expects some exploitation was or could have been happening before the flaw and its fix were first published in October 2025. The UK's NCSC advises investigating for compromise "regardless of when the system was updated." Run F5's built-in sys-eicheck integrity check. F5's own indicators say the changes to /usr/bin/umount and /usr/sbin/httpd make this tool fail, so a failure is itself the signal. Collect a qkview report, send it to F5 and raise a case. Ireland's NCSC said F5 can check that report for signs of compromise, and that raising an associated case brings a quicker and fuller response. Compare the contents of modules in memory against the copies on disk, which Sophos recommends adding to incident response playbooks for critical web servers. Where a full investigation is not possible, the UK NCSC advises isolating the appliance and rebuilding it as new, and says this may cause an outage. Three things are still unknown. F5 has not said when exploitation began. None of the published advisories or analyses say whether upgrading an appliance to a fixed release removes malware already installed on it, and both Sophos and ESET describe a component designed to survive upgrade images. And no one has named an attacker: Sophos said it does not have enough evidence to name a group, and ESET said in April that it had not settled the question either.
5 shared
Sep 9, 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.*
5 shared
Jul 28, 2025