{"id":"CVE-2026-89676","aliases":[],"url":"https://o3.security/vulnerability/CVE-2026-89676","summary":"nfsd: fix stale s2s_cp_stateids IDR entry for async COPY","details":"In the Linux kernel, the following vulnerability has been resolved:\n\nnfsd: fix stale s2s_cp_stateids IDR entry for async COPY\n\nFor an async COPY, nfsd4_copy() called nfs4_init_copy_state() before\ndup_copy_fields(), so the s2s_cp_stateids IDR was pointed at\n&u->copy->cp_stateid -- memory in the per-rqstp COMPOUND buffer that is\nreused by the next request. dup_copy_fields() copies only the value into\nasync_copy, so the IDR slot dangled at the transient buffer for the whole\nbackground copy. Any IDR walker then dereferences reused request memory:\nthe laundromat reads cs_type from it and, if the bytes look like an\nexpired NFS4_COPYNOTIFY_STID, follows into\nrefcount_dec()/idr_remove()/kfree() on garbage; manage_cpntf_state() has\nthe same exposure via idr_find().\n\nDuplicate the fields first, then register the stateid on the stable\nasync_copy. result->cb_stateid is unchanged.","published":"2026-09-11T19:46:00.382Z","modified":"2026-09-14T03:46:24.547108212Z","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":"6.18.50"}],"fix":null,"references":[{"type":"WEB","url":"https://git.kernel.org/stable/c/14b978e8d05ce018d0afbeb6611833ef91713a02"},{"type":"WEB","url":"https://git.kernel.org/stable/c/9b4e5e9ba5ae13808b8a6d229d87c54611ba0e7a"},{"type":"WEB","url":"https://git.kernel.org/stable/c/d0beaee498e11880e72826026db0e9c9890fc114"},{"type":"ADVISORY","url":"https://github.com/CVEProject/cvelistV5/tree/main/cves/2026/89xxx/CVE-2026-89676.json"},{"type":"ADVISORY","url":"https://nvd.nist.gov/vuln/detail/CVE-2026-89676"},{"type":"PACKAGE","url":"https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git"}],"provenance":{"sources":["OSV.dev","FIRST.org (EPSS)"],"lastVerified":"2026-09-14T03:46:24.547108212Z"}}