{"id":"CVE-2026-74590","aliases":[],"url":"https://o3.security/vulnerability/CVE-2026-74590","summary":"fsverity: Fix bpf_get_fsverity_digest() dynptr assumptions","details":"In the Linux kernel, the following vulnerability has been resolved:\n\nfsverity: Fix bpf_get_fsverity_digest() dynptr assumptions\n\nThe BPF verifier and the dynptr abstraction ensure that the memory space\nreferenced by a dynptr remains valid.  They do not, however, provide any\nguarantee that the contents of the memory are stable.  kfuncs are\nexpected to remain memory-safe even if concurrent modifications occur.\n\nbpf_get_fsverity_digest() didn't follow that: it could crash if\narg->digest_size was concurrently modified.\n\nFix that by using the known-good value hash_alg->digest_size instead.\n\nAlso widen 'dynptr_sz' and 'out_digest_sz' to u64 to match the return\ntype of __bpf_dynptr_size().  It doesn't appear that it can actually be\nmore than INT_MAX currently (since __bpf_dynptr_data_rw() excludes\nfile-based pointers), but the correct type might as well be used.","published":"2026-08-22T15:31:41.929Z","modified":"2026-08-24T11:47:00.571873830Z","cvss":null,"epss":null,"cisaKev":null,"exploitsKnown":null,"affectedPackages":[{"ecosystem":"Linux","name":"Kernel","fixedVersion":"6.12.104"}],"fix":null,"references":[{"type":"WEB","url":"https://git.kernel.org/stable/c/1344b632cb5043e32939a84568125719111c5af3"},{"type":"WEB","url":"https://git.kernel.org/stable/c/2a5cfcad1d56e26d645b7887b0ed24c371851525"},{"type":"WEB","url":"https://git.kernel.org/stable/c/3e8ec7c0387273329374f5c7bd61f5f38af71fe1"},{"type":"WEB","url":"https://git.kernel.org/stable/c/5bd63cad9df4328a184c409fbdad4f17944bcdb8"},{"type":"ADVISORY","url":"https://github.com/CVEProject/cvelistV5/tree/main/cves/2026/74xxx/CVE-2026-74590.json"},{"type":"ADVISORY","url":"https://nvd.nist.gov/vuln/detail/CVE-2026-74590"},{"type":"PACKAGE","url":"https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git"}],"provenance":{"sources":["OSV.dev","FIRST.org (EPSS)"],"lastVerified":"2026-08-24T11:47:00.571873830Z"}}