{"id":"CVE-2024-36971","aliases":["A-343727534","ASB-A-343727534"],"url":"https://o3.security/vulnerability/CVE-2024-36971","summary":"net: fix __dst_negative_advice() race","details":"In the Linux kernel, the following vulnerability has been resolved:\n\nnet: fix __dst_negative_advice() race\n\n__dst_negative_advice() does not enforce proper RCU rules when\nsk->dst_cache must be cleared, leading to possible UAF.\n\nRCU rules are that we must first clear sk->sk_dst_cache,\nthen call dst_release(old_dst).\n\nNote that sk_dst_reset(sk) is implementing this protocol correctly,\nwhile __dst_negative_advice() uses the wrong order.\n\nGiven that ip6_negative_advice() has special logic\nagainst RTF_CACHE, this means each of the three ->negative_advice()\nexisting methods must perform the sk_dst_reset() themselves.\n\nNote the check against NULL dst is centralized in\n__dst_negative_advice(), there is no need to duplicate\nit in various callbacks.\n\nMany thanks to Clement Lecigne for tracking this issue.\n\nThis old bug became visible after the blamed commit, using UDP sockets.","published":"2024-06-10T09:03:23.878Z","modified":"2026-10-20T10:31:03.701698862Z","cvss":{"score":7.8,"severity":"HIGH","vector":"CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H"},"epss":{"score":0.02701,"percentile":0.85185,"asOf":"2026-09-16"},"cisaKev":null,"exploitsKnown":2,"affectedPackages":[{"ecosystem":"Linux","name":"Kernel","fixedVersion":"4.19.316"}],"fix":null,"references":[{"type":"WEB","url":"https://git.kernel.org/stable/c/051c0bde9f0450a2ec3d62a86d2a0d2fad117f13"},{"type":"WEB","url":"https://git.kernel.org/stable/c/2295a7ef5c8c49241bff769e7826ef2582e532a6"},{"type":"WEB","url":"https://git.kernel.org/stable/c/5af198c387128a9d2ddd620b0f0803564a4d4508"},{"type":"WEB","url":"https://git.kernel.org/stable/c/81dd3c82a456b0015461754be7cb2693991421b4"},{"type":"WEB","url":"https://git.kernel.org/stable/c/92f1655aa2b2294d0b49925f3b875a634bd3b59e"},{"type":"WEB","url":"https://git.kernel.org/stable/c/b8af8e6118a6605f0e495a58d591ca94a85a50fc"},{"type":"WEB","url":"https://git.kernel.org/stable/c/db0082825037794c5dba9959c9de13ca34cc5e72"},{"type":"WEB","url":"https://git.kernel.org/stable/c/eacb8b195579c174a6d3e12a9690b206eb7f28cf"},{"type":"WEB","url":"https://lists.debian.org/debian-lts-announce/2024/06/msg00020.html"},{"type":"WEB","url":"https://www.cisa.gov/known-exploited-vulnerabilities-catalog?field_cve=CVE-2024-36971"},{"type":"ADVISORY","url":"https://github.com/CVEProject/cvelistV5/tree/main/cves/2024/36xxx/CVE-2024-36971.json"},{"type":"ADVISORY","url":"https://nvd.nist.gov/vuln/detail/CVE-2024-36971"},{"type":"PACKAGE","url":"https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git"}],"provenance":{"sources":["OSV.dev","FIRST.org (EPSS)"],"lastVerified":"2026-10-20T10:31:03.701698862Z"}}