{"id":"CVE-2026-89639","aliases":[],"url":"https://o3.security/vulnerability/CVE-2026-89639","summary":"cifs: use cifs_invalidate_cache() in cifs_do_truncate() for O_TRUNC","details":"In the Linux kernel, the following vulnerability has been resolved:\n\ncifs: use cifs_invalidate_cache() in cifs_do_truncate() for O_TRUNC\n\ncifs_do_truncate() is invoked from cifs_open() without i_rwsem, so it\ncannot use cifs_resize_file_locked() to perform a proper fscache cookie\nresize.  Instead, add cifs_invalidate_cache() after cifs_setsize().\n\ncifs_invalidate_cache() calls fscache_invalidate(), which works without\nholding i_rwsem: it unconditionally increments inval_counter and sets\nFSCACHE_COOKIE_NO_DATA_TO_READ, ensuring that stale cached data is not\nserved once the cookie is later activated by fscache_use_cookie().\nTruncation to zero leaves no valid cached data, making invalidation the\ncorrect semantic here.","published":"2026-09-11T19:45:32.532Z","modified":"2026-09-14T03:46:20.489762323Z","cvss":{"score":7.1,"severity":"HIGH","vector":"CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:N"},"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/364b183230586a62660a7280c1eb20138338eeb5"},{"type":"WEB","url":"https://git.kernel.org/stable/c/81fc3868a7f726980ff845c1d0d271051e5f0f45"},{"type":"WEB","url":"https://git.kernel.org/stable/c/8b9b10fe5b8b492b27b9f4546742ea541a650213"},{"type":"ADVISORY","url":"https://github.com/CVEProject/cvelistV5/tree/main/cves/2026/89xxx/CVE-2026-89639.json"},{"type":"ADVISORY","url":"https://nvd.nist.gov/vuln/detail/CVE-2026-89639"},{"type":"PACKAGE","url":"https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git"}],"provenance":{"sources":["OSV.dev","FIRST.org (EPSS)"],"lastVerified":"2026-09-14T03:46:20.489762323Z"}}