Search/CISA alerts of active exploitation of three Linux kernel flaws
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CISA alerts of active exploitation of three Linux kernel flaws

The U.S. Cybersecurity and Infrastructure Security Agency (CISA) is warning that hackers are exploiting three Linux kernel vulnerabilities, one of them rated critical. The three security issues were added separately last week and have severity ratings ranging from medium to critical. One of them, tracked as CVE-2025-39964, existed in the Linux kernel for 14 years. CISA marked all three flaws with the highest priority for federal agencies, ordering them to apply available security updates and mitigations by the end of today. The three vulnerabilities are: CVE-2025-39964: a race condition in the kernel’s AF_ALG cryptographic socket interface that allows concurrent writes to corrupt per-socket state and potentially crash systems or alter cryptographic results. CVE-2026-53266: an…

CVEs
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Highest CVSS
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CVE-2026-87902: Critical Vulnerability in WordPress
A critical vulnerability has been discovered in the popular WordPress content management system that allows attackers to execute arbitrary code on the web server. The vulnerability has been assigned the number CVE-2026-87902. The good news is that on September 22, WordPress released an update that patches it. The bad news is that the first attempts to exploit CVE-2026-87902 were detected just a few hours after the patch was released. Therefore, all companies whose corporate websites or blogs run on this platform are advised to update immediately. WordPress versions affected by CVE-2026-87902 According to data published by WordPress on GitHub, all versions of the CMS from 4.7.0 through 7.1.1 are vulnerable. The company has released updates for all supported branches of the system; a complete table listing the patched version numbers can be found on the company’s GitHub page . The latest version of WordPress should be updated to version 7.1.2 (or newer). What’s the nature of the CVE-2026-87902 vulnerability, and why is it so dangerous? Under normal circumstances, WordPress loads PHP template files only from a specific folder within the active theme. However, due to the CVE-2026-87902 vulnerability, an attacker can craft a request to WordPress in such a way that an arbitrary PHP file is included — without requiring any authorization. Yes, the file must already be uploaded to the targeted server in some way, but that’s not really a problem for an attacker. It sounds like a path traversal vulnerability, but in most publications, CVE-2026-87902 is classified as an RCE (Remote Code Execution) vulnerability because, under certain WordPress and PHP server configurations, the attack can lead to the execution of arbitrary code. How to stay safe The only way to secure a corporate WordPress site is to install the latest version. The researcher who discovered the vulnerability also offers several tips for hardening CMS security, but emphasizes that these are meant to complement the patch, not replace it. The Hacker News lists several PHP filenames and IP addresses used in the attack via CVE-2026-87902. These can serve as indicators that a WordPress instance has been compromised. Given that only a few hours pass between the publication of information about a vulnerability’s existence and the start of attacks exploiting it, it’s crucial for companies to have a properly configured, centralized vulnerability management system. To achieve this, they should have a specialized solution capable of identifying and resolving vulnerabilities, prioritizing them based on actual risks, and automating remediation processes.
kaspersky.comSep 25, 2026extracted
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WordPress Patches ‘Click2Shell’ Vulnerability
Attacker compromised nearly 1000 Zyxel switches since August (CVE-2026-7273) A Chinese-speaking threat actor has exploited a vulnerability (CVE-2026-7273) in unpatched ZyXEL GS1900 Smart Managed Switches and has exfiltrated sensitive data from 996 devices across 48 countries, GreyNoise reported on Monday. The affected switches are predominantly located in Italy, the US, Taiwan, South Korea, and a number of EU countries. CVE-2026-7273 exploitation is part of an unfolding operation The Zyxel GS1900 Series is a line of Gigabit Ethernet switches aimed at small and mid-sized business networks. They are typically deployed at small offices, schools, hotels, and retail shops. CVE-2026-7273 is a stack-based buffer overflow vulnerability affecting Zyxel GS1900 switches running firmware versions 2.90(XXXX.1)C0 and earlier. It allows a LAN-based, unauthenticated attacker to execute OS commands on the device via a specially crafted HTTP request. The privately reported vulnerability was fixed in June 2026, when Zyxel released new firmware versions with the patch. The attacks exploiting CVE-2026-7273 happened on or about 17 August, GreyNoise said, and the threat actor grabbed compromised devices’ configuration, networking information, and hashed root level credentials. (According to GreyNoise, 564 of these victims had factory default credentials.) “The exploit code was contained within a Python script which was heavily obfuscated by the commercial obfuscation tool PyArmor,” the researchers shared. After deobfuscating it, they discovered it explicitly targets firmware versions 2.10 through 2.90 of the GS1900-24, but “it does provide command line options (e.g. libc base address, global offsets), for targeting other firmware in scope for the vulnerability.” GreyNoise tied this exploitation activity to a threat actor that is related or the same one that, earlier this year, targeted WordPress setups through CVE-2026-63030 and CVE-2026-60137 (the WP2Shell” exploit chain), and compromised Internet-facing Gitea instances via CVE-2026-60004. After breaching WordPress installations of 49 organizations across 29 countries, in at least one instance the threat actor deployed a custom web shell, stole WP administrator accounts, credentials, exfiltrated data from SQL databases, and added a new admin account. After successfully targeting Gitea instances, the threat actor exfiltrated source code, credentials, established persistent access, and leveraged it for lateral movement. CISA added CVE-2026-7273 – the Zyxel flaw – to its Known Exploited Vulnerabilities catalog, and ordered US civilian federal agencies to address it by September 24, 2026 and check for indicators of compromise. GreyNoise has shared a list of them, though one IP address involved in the exploitation remains redacted. “We are withholding the exact IP address due to victim sensitivities and operational risk. Once these factors have been mitigated, GreyNoise will publish an update,” the company said. Also under attack: Veeam Agent for Windows In other “active exploitation” news, Arctic Wolf says that attackers are exploiting CVE-2026-32996, a local privilege escalation vulnerability in Veeam (backup) Agent for Microsoft Windows, but has not shared details about the attacks. “Arctic Wolf recommends prioritising remediation on shared workstations, servers, administrator workstations, and systems where local user access is available, or where compromise of a low-privileged account could lead to endpoint takeover,” they advised. “Upgrade Veeam Backup & Replication to 13.0.2.29 or later. This will also update the Veeam Agent for Windows to build 13.0.3.1220, which contains the fix.” We’ve reached out to Arctic Wolf for more information, and we’ll update this article when we hear back from them. Subscribe to our breaking news e-mail alert to never miss out on the latest breaches, vulnerabilities and cybersecurity threats. Subscribe here!
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Sep 22, 2026