{"id":"CVE-2026-99131","aliases":[],"title":"xfs: fix capability check in xfs","titleSource":"Linux","descriptionSource":"Linux","products":[{"vendor":"Linux","name":"Linux","platforms":[],"versions":[{"version":"eba0549bc7d100691c13384b774346b8aa9cf9a9","status":"affected","lessThan":"19a1a22029ad3ae3604c763af6bd1195cb73648f","versionType":"git"},{"version":"eba0549bc7d100691c13384b774346b8aa9cf9a9","status":"affected","lessThan":"7809ac0161c7c5f52ed348fb1ec683b2b454a83e","versionType":"git"},{"version":"eba0549bc7d100691c13384b774346b8aa9cf9a9","status":"affected","lessThan":"e2f62a9744ebad3bcb6347a648e615026e9efeff","versionType":"git"}],"defaultStatus":"unaffected","source":"Linux","url":"https://www.cve.org/CVERecord?id=CVE-2026-99131"},{"vendor":"Linux","name":"Linux","platforms":[],"versions":[{"version":"5.18","status":"affected"},{"version":"0","status":"unaffected","lessThan":"5.18","versionType":"semver"},{"version":"6.18.59","status":"unaffected","lessThanOrEqual":"6.18.*","versionType":"semver"},{"version":"7.2.13","status":"unaffected","lessThanOrEqual":"7.2.*","versionType":"semver"},{"version":"7.3","status":"unaffected","lessThanOrEqual":"*","versionType":"original_commit_for_fix"}],"defaultStatus":"affected","source":"Linux","url":"https://www.cve.org/CVERecord?id=CVE-2026-99131"}],"remediation":[],"description":"In the Linux kernel, the following vulnerability has been resolved:\n\nxfs: fix capability check in xfs\n\nAn user reported a bug where he managed to evade group's quota\nby changing a file's gid to a different group id the same user\nbelonged to, even though quotas were enforced on both gids and the\nfile's size was big enough to exceed the quota's hardlimit.\n\nCommit eba0549bc7d1 replaced a capable() call by a\nhas_capability_noaudit() to prevent unnecessary selinux audit messages.\nTurns out that both calls have slightly different semantics even though\ntheir documentation seems similar. Where in a nutshell:\n\ncapable() - Tests the task's effective credentials\nhas_ns_capability_noaudit() - Tests the task's real credentials\n\nThis most of the time has no practical difference but in some cases like\nchanging attrs (specifically group id in this case) through a NFS client\nthis will allow the quota code to use XFS_QMOPT_FORCE_RES, effectively\nbypassing quota accounting checks.\n\nUsing instead ns_capable_noaudit() should fix this issue and prevent\nselinux audit messages.\n\nThis also fix the remaining calls to has_capability_noaudit()","severity":"unknown","score":null,"published":"2026-10-28T10:34:45.102Z","modified":"2026-10-28T10:34:45.102Z","withdrawn":false,"knownExploited":false,"affected":[],"references":["https://git.kernel.org/stable/c/19a1a22029ad3ae3604c763af6bd1195cb73648f","https://git.kernel.org/stable/c/7809ac0161c7c5f52ed348fb1ec683b2b454a83e","https://git.kernel.org/stable/c/e2f62a9744ebad3bcb6347a648e615026e9efeff"],"sources":[{"name":"CVE","id":"CVE-2026-99131","modified":"2026-10-28T10:34:45.102Z","url":"https://www.cve.org/CVERecord?id=CVE-2026-99131"}],"assessments":[],"sourceAffected":[],"kev":{"status":"not-listed","checkedAt":"2026-10-28T23:20:36.067Z"},"coverage":[{"source":"NVD","status":"not-checked"},{"source":"GHSA","status":"not-checked"},{"source":"EUVD","status":"not-checked"},{"source":"EPSS","status":"not-checked"}],"evidence":[]}