{"id":"CVE-2026-93138","aliases":[],"url":"https://o3.security/vulnerability/CVE-2026-93138","summary":"bpf: Fix vmlinux BTF prep race in bpf_get_btf_vmlinux","details":"In the Linux kernel, the following vulnerability has been resolved:\n\nbpf: Fix vmlinux BTF prep race in bpf_get_btf_vmlinux\n\nbpf_get_btf_vmlinux() lazily parses the vmlinux BTF under the\nbpf_verifier_lock, but publishes the result through a plain store\nand re-checks it through a plain lockless load. Nothing orders\nthe stores initializing the struct btf inside btf_parse_vmlinux()\nagainst the store publishing the pointer: On a weakly ordered\narch, a concurrent first-time caller taking the lockless fast\npath could in principle observe the pointer before the parsed\ncontents are visible. The mutex_unlock() does not help such a\nreader given it only synchronizes with a later acquisition of the\nsame lock. Thus, publish the pointer with smp_store_release()\nand read it on the fast path with smp_load_acquire().\n\nAcquire semantics are needed rather than a dependency-ordered\nREAD_ONCE(): btf_parse_vmlinux() also populates globals outside\nthe returned object (e.g. bpf_ctx_convert.t). An address\ndependency would only order accesses performed through the\npointer and not cover other globals.","published":"2026-09-17T16:11:38.795Z","modified":"2026-09-19T03:47:27.898608009Z","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":null,"cisaKev":null,"exploitsKnown":null,"affectedPackages":[{"ecosystem":"Linux","name":"Kernel","fixedVersion":"5.10.270"}],"fix":null,"references":[{"type":"WEB","url":"https://git.kernel.org/stable/c/2892f3f44bf865c8fb6b6c0960edec4cc91806ee"},{"type":"WEB","url":"https://git.kernel.org/stable/c/86d11c594d60b255b526fa5260f669463fb1a063"},{"type":"WEB","url":"https://git.kernel.org/stable/c/92863e678070f57c17c868e4bfa2441a5c61ad2b"},{"type":"WEB","url":"https://git.kernel.org/stable/c/978524ecfc1c539282df5858de1eec20748c6f74"},{"type":"WEB","url":"https://git.kernel.org/stable/c/a7fe72d780122eb934536f1719abad445f6afdf7"},{"type":"WEB","url":"https://git.kernel.org/stable/c/e18a10b39c994f04e1ebd7f8fc042bb1ca8ad053"},{"type":"WEB","url":"https://git.kernel.org/stable/c/eaf302628a78806f66d8224d6ba03fb4d5025de4"},{"type":"WEB","url":"https://git.kernel.org/stable/c/f32a4a40bc635be25d6816da4bd91e9e58c31bf3"},{"type":"ADVISORY","url":"https://github.com/CVEProject/cvelistV5/tree/main/cves/2026/93xxx/CVE-2026-93138.json"},{"type":"ADVISORY","url":"https://nvd.nist.gov/vuln/detail/CVE-2026-93138"},{"type":"PACKAGE","url":"https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git"}],"provenance":{"sources":["OSV.dev","FIRST.org (EPSS)"],"lastVerified":"2026-09-19T03:47:27.898608009Z"}}