Description

The US cybersecurity agency CISA has issued a warning about active exploitation of a recent Linux kernel vulnerability, CVE-2024-1086. This use-after-free flaw in the ‘netfilter: nf_tables’ component allows local attackers to elevate privileges. Linux kernel versions from 5.14 to 6.6 are affected, with the issue potentially impacting all versions since 3.15. Patches were released in February 2024, affecting AlmaLinux, Debian, Gentoo, Red Hat, SUSE, and Ubuntu, among others. In March 2024, Notselwyn, the bug hunter who discovered CVE-2024-1086, published proof-of-concept (PoC) code with a 99.4% success rate, highlighting the flaw's ease of exploitation. The bug, a double-free issue due to insufficient input sanitization in netfilter, allows a kernel-space mirroring attack (KSMA) from userland using the Dirty Pagedirectory technique, leading to crashes or arbitrary code execution in the kernel. On May 30, 2024, CISA added CVE-2024-1086 to its Known Exploited Vulnerabilities (KEV) catalog, noting that threat actors are actively targeting it. No ransomware attacks or specific details about the exploitation have been disclosed. Under Binding Operational Directive (BOD) 22-01, federal agencies must apply patches or mitigations by June 20. CISA urges all organizations to prioritize remediation to reduce cyberattack risks, emphasizing the importance of timely patching to mitigate exposure.