{"id":"CVE-2026-89711","revision":null,"records":[{"revision":"a38572c0d746423c8bb0ea1caa6a7753","observedAt":"2026-10-23T15:48:27.903+00:00","statement":{"source":"cve-program","id":"CVE-2026-89711","aliases":[],"title":"NFSD: remove flawed WARN_ON_ONCE from nfsd_mode_check","description":"In the Linux kernel, the following vulnerability has been resolved:\n\nNFSD: remove flawed WARN_ON_ONCE from nfsd_mode_check\n\nThe header for commit e75b23f9e323 (\"nfsd: check d_can_lookup in\nfh_verify of directories\") details the assumption that justified\nadding the WARN_ON_ONCE to nfsd_mode_check(), that assumption is\ninvalid (in the case of NFS reexport).\n\nWhen NFSD exports an NFS filesystem it is very possible for\nnfsd_mode_check() to encounter a @dentry that doesn't have\ni_op->lookup (see nfs_fhget()'s NFS_ATTR_FATTR_MOUNTPOINT and\nNFS_ATTR_FATTR_V4_REFERRAL handling, and d_flags_for_inode()).\n\nSo remove nfsd_mode_check()'s WARN_ON_ONCE(). The nfserr_notdir\nreturn on that branch must stay. It guards the subsequent\nlookup_one_unlocked() -> __lookup_slow() path, which calls\ninode->i_op->lookup() with no NULL check, so returning nfserr_notdir\nis what keeps a client LOOKUP into such a @dentry from dereferencing\na NULL method pointer.","state":0,"publishedAt":"2026-09-11T19:46:26.269+00:00","modifiedAt":"2026-10-19T08:51:24.221+00:00","affected":[{"ecosystem":"Vendor product","name":"Linux","ranges":[],"versions":[],"rawVersionEvidence":"{\n \"product\": \"Linux\",\n \"vendor\": \"Linux\",\n \"defaultStatus\": \"unaffected\",\n \"repo\": \"https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git\",\n \"programFiles\": [\n \"fs/nfsd/nfsfh.c\"\n ],\n \"versions\": [\n {\n \"version\": \"e75b23f9e323b1e0759619c39d5a9f7a3a5d9d2c\",\n \"lessThan\": \"ae251937c6f0237e5b555a5e4ba4595b8206e865\",\n \"status\": \"affected\",\n \"versionType\": \"git\"\n },\n {\n \"version\": \"e75b23f9e323b1e0759619c39d5a9f7a3a5d9d2c\",\n \"lessThan\": \"e145e8d67a5d41c72d322e7f87ab474d39d9dfb7\",\n \"status\": \"affected\",\n \"versionType\": \"git\"\n },\n {\n \"version\": \"e75b23f9e323b1e0759619c39d5a9f7a3a5d9d2c\",\n \"lessThan\": \"9f4434893a2783f7384d993cea883aff3fb7a52d\",\n \"status\": \"affected\",\n \"versionType\": \"git\"\n },\n {\n \"version\": \"e75b23f9e323b1e0759619c39d5a9f7a3a5d9d2c\",\n \"lessThan\": \"2ef131323999539038e306773c8256403834361b\",\n \"status\": \"affected\",\n \"versionType\": \"git\"\n },\n {\n \"version\": \"e75b23f9e323b1e0759619c39d5a9f7a3a5d9d2c\",\n \"lessThan\": \"b55b4d880bb080fa10eb08ba21a5d8679b8102fe\",\n \"status\": \"affected\",\n \"versionType\": \"git\"\n },\n {\n \"version\": \"e75b23f9e323b1e0759619c39d5a9f7a3a5d9d2c\",\n \"lessThan\": \"7ef182a8fe9c12b0d936880b1e504840639aa009\",\n \"status\": \"affected\",\n \"versionType\": \"git\"\n },\n {\n \"version\": \"e75b23f9e323b1e0759619c39d5a9f7a3a5d9d2c\",\n \"lessThan\": \"a275de3bac5635514ca830f2e46b5ff0e66b5c4c\",\n \"status\": \"affected\",\n \"versionType\": \"git\"\n },\n {\n \"version\": \"e75b23f9e323b1e0759619c39d5a9f7a3a5d9d2c\",\n \"lessThan\": \"aa0cf48a448c5a9fe1a1e880899ecd589ce39e6e\",\n \"status\": \"affected\",\n \"versionType\": \"git\"\n }\n ]\n }"},{"ecosystem":"Vendor product","name":"Linux","ranges":[],"versions":[],"rawVersionEvidence":"{\n \"product\": \"Linux\",\n \"vendor\": \"Linux\",\n \"defaultStatus\": \"affected\",\n \"repo\": \"https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git\",\n \"programFiles\": [\n \"fs/nfsd/nfsfh.c\"\n ],\n \"versions\": [\n {\n \"version\": \"4.8\",\n \"status\": \"affected\"\n },\n {\n \"version\": \"0\",\n \"lessThan\": \"4.8\",\n \"status\": \"unaffected\",\n \"versionType\": \"semver\"\n },\n {\n \"version\": \"5.10.270\",\n \"lessThanOrEqual\": \"5.10.*\",\n \"status\": \"unaffected\",\n \"versionType\": \"semver\"\n },\n {\n \"version\": \"5.15.221\",\n \"lessThanOrEqual\": \"5.15.*\",\n \"status\": \"unaffected\",\n \"versionType\": \"semver\"\n },\n {\n \"version\": \"6.1.188\",\n \"lessThanOrEqual\": \"6.1.*\",\n \"status\": \"unaffected\",\n \"versionType\": \"semver\"\n },\n {\n \"version\": \"6.6.157\",\n \"lessThanOrEqual\": \"6.6.*\",\n \"status\": \"unaffected\",\n \"versionType\": \"semver\"\n },\n {\n \"version\": \"6.12.109\",\n \"lessThanOrEqual\": \"6.12.*\",\n \"status\": \"unaffected\",\n \"versionType\": \"semver\"\n },\n {\n \"version\": \"6.18.50\",\n \"lessThanOrEqual\": \"6.18.*\",\n \"status\": \"unaffected\",\n \"versionType\": \"semver\"\n },\n {\n \"version\": \"7.2.4\",\n \"lessThanOrEqual\": \"7.2.*\",\n \"status\": \"unaffected\",\n \"versionType\": \"semver\"\n },\n {\n \"version\": \"7.3\",\n \"lessThanOrEqual\": \"*\",\n \"status\": \"unaffected\",\n \"versionType\": \"original_commit_for_fix\"\n }\n ]\n }"}],"metrics":[{"system":"CVSS 3.1","vector":"CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:L/I:N/A:H","score":8.2,"severity":"HIGH"}],"references":["https://git.kernel.org/stable/c/ae251937c6f0237e5b555a5e4ba4595b8206e865","https://git.kernel.org/stable/c/e145e8d67a5d41c72d322e7f87ab474d39d9dfb7","https://git.kernel.org/stable/c/9f4434893a2783f7384d993cea883aff3fb7a52d","https://git.kernel.org/stable/c/2ef131323999539038e306773c8256403834361b","https://git.kernel.org/stable/c/b55b4d880bb080fa10eb08ba21a5d8679b8102fe","https://git.kernel.org/stable/c/7ef182a8fe9c12b0d936880b1e504840639aa009","https://git.kernel.org/stable/c/a275de3bac5635514ca830f2e46b5ff0e66b5c4c","https://git.kernel.org/stable/c/aa0cf48a448c5a9fe1a1e880899ecd589ce39e6e"],"sourceUrl":"https://www.cve.org/CVERecord?id=CVE-2026-89711","license":"CVE Program Terms of Use","key":"cve-program:CVE-2026-89711","identifiers":["CVE-2026-89711"]},"retained":false,"historicalAffected":[]}],"coverage":[{"source":"cisa-kev:global","scope":"Complete CISA KEV catalog; all vendors. Missing entries do not establish absence of exploitation.","generation":"2026-11-09T04:03:51.7811525+00:00","complete":true,"records":1769,"lastAttemptAt":"2026-11-09T04:03:51.7811525+00:00","lastSuccessAt":"2026-11-09T04:03:51.9477173+00:00","error":null,"lastVerifiedAt":"2026-11-09T04:03:51.9477231+00:00","snapshotPublishedAt":null,"importing":false,"stagedRecords":0,"checkedIdentifiers":null,"expectedIdentifiers":null,"failedIdentifiers":null},{"source":"cve-program","scope":"Official CVE Program baseline and cumulative hourly delta; all vendors, published and rejected records","generation":"cve-24e6fde7b744113daefb8f6135035fb8a5c69c9617c9c0d40574a0376532ffd3-246bcd291098e4bae24ec491a133b97526d1f4514f8eb34817e1ec280d43b276","complete":true,"records":421286,"lastAttemptAt":"2026-11-09T04:02:14.2951792+00:00","lastSuccessAt":"2026-11-09T04:02:14.2751612+00:00","error":null,"lastVerifiedAt":"2026-11-09T04:02:14.2951792+00:00","snapshotPublishedAt":"2026-11-09T03:29:47+00:00","importing":false,"stagedRecords":0,"checkedIdentifiers":null,"expectedIdentifiers":null,"failedIdentifiers":null},{"source":"euvd","scope":"Rolling EUVD lookups of CVE aliases in current public OSV archives; 500 identifiers per refresh, rechecked after 48 hours. Not a global EUVD catalog. Successful not-found lookups count as checked; they do not imply withdrawal or safety. No reader inventory is sent.","generation":"enrichment-0e1130a95bab4b43bc10624fd5ee853a","complete":false,"records":13654,"lastAttemptAt":"2026-11-09T04:16:03.8367163+00:00","lastSuccessAt":"2026-11-09T04:16:03.832+00:00","error":"8 identifier lookups failed; latest failures include HTTP 403. Other identifiers were checked independently.","lastVerifiedAt":"2026-11-09T04:16:03.832+00:00","snapshotPublishedAt":null,"importing":false,"stagedRecords":0,"checkedIdentifiers":13653,"expectedIdentifiers":13706,"failedIdentifiers":8},{"source":"first-epss:nuget","scope":"FIRST EPSS for explicit CVE aliases in the collected public NuGet archive. Not a global EPSS backfill.","generation":"2026-11-09T04:03:51.7811525+00:00","complete":true,"records":1096,"lastAttemptAt":"2026-11-09T04:03:51.7811525+00:00","lastSuccessAt":"2026-11-09T04:03:51.948408+00:00","error":null,"lastVerifiedAt":"2026-11-09T04:03:51.9484081+00:00","snapshotPublishedAt":null,"importing":false,"stagedRecords":0,"checkedIdentifiers":null,"expectedIdentifiers":null,"failedIdentifiers":null},{"source":"nvd","scope":"Rolling NVD lookups of CVE aliases in current public OSV archives; 500 identifiers per refresh, rechecked after 48 hours. Not a global NVD catalog. Successful not-found lookups count as checked; they do not imply withdrawal or safety. No reader inventory is sent.","generation":"enrichment-5a44a451442747cb81d83104fe1e7771","complete":true,"records":13666,"lastAttemptAt":"2026-11-09T04:03:52.3882913+00:00","lastSuccessAt":"2026-11-09T02:08:52.274+00:00","error":null,"lastVerifiedAt":"2026-11-09T02:08:52.274+00:00","snapshotPublishedAt":null,"importing":false,"stagedRecords":0,"checkedIdentifiers":13706,"expectedIdentifiers":13706,"failedIdentifiers":0},{"source":"osv:Go","scope":"Complete OSV Go ecosystem archive, including withdrawn and malicious-package source records; statement counts are not unique CVE counts","generation":"go-980593e6977a6d1b4fb1eed5a1ffe88a468736f89f0a06f710924ad59132c023","complete":true,"records":9914,"lastAttemptAt":"2026-11-09T04:03:51.3592849+00:00","lastSuccessAt":"2026-11-08T11:07:07.068788+00:00","error":null,"lastVerifiedAt":"2026-11-09T04:03:51.3592849+00:00","snapshotPublishedAt":"2026-11-08T11:02:46+00:00","importing":false,"stagedRecords":0,"checkedIdentifiers":null,"expectedIdentifiers":null,"failedIdentifiers":null},{"source":"osv:NuGet","scope":"Complete OSV NuGet ecosystem archive, including GitHub Advisory Database records; NuGet version matching only","generation":"nuget-fde804134ecdda0ddd5ff5c26ee1fff5a6fa659311f7ef2e51c6ad54964db0e2","complete":true,"records":1971,"lastAttemptAt":"2026-11-09T04:02:14.6671491+00:00","lastSuccessAt":"2026-11-06T19:03:17.0399903+00:00","error":null,"lastVerifiedAt":"2026-11-09T04:02:14.6671491+00:00","snapshotPublishedAt":"2026-11-06T18:17:57+00:00","importing":false,"stagedRecords":0,"checkedIdentifiers":null,"expectedIdentifiers":null,"failedIdentifiers":null},{"source":"osv:crates.io","scope":"Complete OSV crates.io ecosystem archive, including withdrawn and malicious-package source records; statement counts are not unique CVE counts","generation":"crates.io-3b1150af6d7ada2c07356cbab4ead5224c1485027890f71c71d0742cddf0b9e8","complete":true,"records":3055,"lastAttemptAt":"2026-11-09T04:03:51.7519249+00:00","lastSuccessAt":"2026-11-09T00:02:23.4330288+00:00","error":null,"lastVerifiedAt":"2026-11-09T04:03:51.7519249+00:00","snapshotPublishedAt":"2026-11-08T23:17:54+00:00","importing":false,"stagedRecords":0,"checkedIdentifiers":null,"expectedIdentifiers":null,"failedIdentifiers":null},{"source":"osv:npm","scope":"Complete OSV npm ecosystem archive, including withdrawn and malicious-package source records; statement counts are not unique CVE counts","generation":"npm-6a1c845b1938b1aa788f0e95c9ac8a8d5a1f07caed5d155840b0616b548c1455","complete":true,"records":231296,"lastAttemptAt":"2026-11-09T04:03:51.2380069+00:00","lastSuccessAt":"2026-11-09T04:03:49.859595+00:00","error":null,"lastVerifiedAt":"2026-11-09T04:03:51.2380069+00:00","snapshotPublishedAt":"2026-11-09T03:33:06+00:00","importing":false,"stagedRecords":0,"checkedIdentifiers":null,"expectedIdentifiers":null,"failedIdentifiers":null}]}