All news with #linux kernel tag

CISA: High-Severity Linux Privilege Flaw Used by Ransomware

🔒 CISA confirmed that CVE-2024-1086, a high-severity use-after-free bug in the nf_tables component of the Linux kernel, is being exploited in ransomware campaigns. The flaw, introduced in 2014 and patched in January 2024, enables local attackers to escalate to root. A publicly released PoC targets kernels 5.14–6.6. CISA added the issue to its KEV list and recommended mitigations such as blocklisting nf_tables, restricting user namespaces, or loading the LKRG module.

Deep Dive: BPF LPM Trie Performance and Optimization

🔍 Cloudflare investigated a production soft lockup traced to the Linux BPF LPM trie, a core data structure for IP and IP+Port longest-prefix matching. Benchmarks on 96-core AMD EPYC hardware showed lookups remain relatively fast at modest sizes, but updates, deletes and especially freeing maps degrade severely at scale, causing multi-second CPU stalls and customer packet loss. The post refreshes trie basics, presents measured results (lookups, updates, deletes, free costs), and diagnoses kernel implementation limits — notably binary child pointers, absent level compression, and allocator-induced cache and dTLB pressure — then outlines plans to upstream benchmarks and refactor toward a level-compressed multibit trie to reduce traversal height, cache/TLB misses, and freeing overhead.

CISA Adds Seven CVEs to Known Exploited Vulnerabilities

🔒 CISA has added seven vulnerabilities to its Known Exploited Vulnerabilities (KEV) Catalog after observing evidence of active exploitation. The newly listed entries include CVE-2010-3765, CVE-2010-3962, CVE-2011-3402, CVE-2013-3918, CVE-2021-22555, CVE-2021-43226, and CVE-2025-61882, impacting Mozilla, Microsoft, the Linux Kernel, and Oracle E-Business Suite. Federal Civilian Executive Branch agencies must remediate these vulnerabilities under BOD 22-01, and CISA strongly urges all organizations to prioritize timely remediation as part of routine vulnerability management.

CISA Adds Three CVEs to Known Exploited Vulnerabilities

🔔 CISA has added three vulnerabilities to its Known Exploited Vulnerabilities (KEV) Catalog: CVE-2025-38352 (Linux kernel TOCTOU race condition), CVE-2025-48543 (Android Runtime unspecified vulnerability), and CVE-2025-53690 (Sitecore multiple-products deserialization). Under BOD 22-01, Federal Civilian Executive Branch agencies must remediate cataloged CVEs by the required due dates. Although the directive applies to FCEB agencies, CISA strongly urges all organizations to prioritize timely remediation, patching, and vulnerability management to reduce exposure to active exploitation.

Google fixes actively exploited Android flaws in September

🔒 Google has released the September 2025 Android security update addressing 84 vulnerabilities, including two zero-day flaws observed in limited, targeted exploitation: CVE-2025-38352 (Linux kernel) and CVE-2025-48543 (Android Runtime). The bulletin also patches four critical issues — including an RCE in the System component and three Qualcomm vulnerabilities affecting modem and data stacks. Users are urged to install security patch level 2025-09-01 or 2025-09-05 via Settings > System > Software updates > System update.