{"id":"CVE-2026-89669","aliases":[],"url":"https://o3.security/vulnerability/CVE-2026-89669","summary":"nfsd: initialize copy-notify stateid before publishing it","details":"In the Linux kernel, the following vulnerability has been resolved:\n\nnfsd: initialize copy-notify stateid before publishing it\n\nnfsd4_copy_notify() finished initializing the cpntf state after\nnfs4_alloc_init_cpntf_state() had already linked it into the\ns2s_cp_stateids IDR and the parent's sc_cp_list, with cs_count == 1 (the\nmembership reference) and none held for the caller. A racing\nOFFLOAD_CANCEL (crafted cl_id == nn->s2s_cp_cl_id plus the guessable\nso_id) could reach manage_cpntf_state() and free the entry, turning the\ncaller's subsequent cpn_cnr_stateid read and cp_p_stateid/cp_p_clid\nwrites into use-after-free. The owning clientid was also only recorded\nafter publication, so it could not gate an ownership check in that window.\n\nRecord cp_p_stateid and cp_p_clid inside nfs4_alloc_init_cpntf_state()\nbefore nfs4_init_cp_state() publishes the entry, and return it with an\nextra reference. The caller reads the stateid under that reference and\ndrops it with nfs4_put_cpntf_state(); on a late error the laundromat\nreaps the entry.","published":"2026-09-11T19:45:55.111Z","modified":"2026-09-14T03:45:36.643175235Z","cvss":{"score":9.8,"severity":"CRITICAL","vector":"CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H"},"epss":null,"cisaKev":null,"exploitsKnown":null,"affectedPackages":[{"ecosystem":"Linux","name":"Kernel","fixedVersion":"6.12.109"}],"fix":null,"references":[{"type":"WEB","url":"https://git.kernel.org/stable/c/129643893b79f8a3c6b72045f933fbab5ee424ca"},{"type":"WEB","url":"https://git.kernel.org/stable/c/4cdef96892f4fa6e70c405b6e8f2fd6972f3b64b"},{"type":"WEB","url":"https://git.kernel.org/stable/c/a4d7fedcaaf33e60a01e53eafca9041ef966212f"},{"type":"WEB","url":"https://git.kernel.org/stable/c/e08a3dcaca0505f861e344a387f37f94d95dbdc2"},{"type":"ADVISORY","url":"https://github.com/CVEProject/cvelistV5/tree/main/cves/2026/89xxx/CVE-2026-89669.json"},{"type":"ADVISORY","url":"https://nvd.nist.gov/vuln/detail/CVE-2026-89669"},{"type":"PACKAGE","url":"https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git"}],"provenance":{"sources":["OSV.dev","FIRST.org (EPSS)"],"lastVerified":"2026-09-14T03:45:36.643175235Z"}}