CVE-2026-90039

{"dataType": "CVE_RECORD", "dataVersion": "5.2", "cveMetadata": {"cveId": "CVE-2026-90039", "assignerOrgId": "416baaa9-dc9f-4396-8d5f-8c081fb06d67", "state": "PUBLISHED", "assignerShortName": "Linux", "dateReserved": "2026-09-11T19:38:34.783Z", "datePublished": "2026-09-16T10:33:38.091Z", "dateUpdated": "2026-10-19T08:56:56.714Z"}, "containers": {"cna": {"providerMetadata": {"orgId": "416baaa9-dc9f-4396-8d5f-8c081fb06d67", "shortName": "Linux", "dateUpdated": "2026-10-19T08:56:56.714Z"}, "descriptions": [{"lang": "en", "value": "In the Linux kernel, the following vulnerability has been resolved:\n\nNFSD: Guard admin state-revocation walks with NFSD_NET_UP\n\nWriting to /proc/fs/nfsd/unlock_filesystem, or sending the\nNFSD_CMD_UNLOCK_FILESYSTEM or NFSD_CMD_UNLOCK_EXPORT netlink command,\nwalks the NFSv4 client hash tables to revoke open state and cancel\nasync COPY operations. All three handlers gate that walk on\nnn->nfsd_serv, but a listener added via portlist or netlink\nlistener_set sets nn->nfsd_serv before any nfsd thread starts.\nnfsd_startup_net() has not yet allocated nn->conf_id_hashtbl, so the\nwalkers dereference a NULL table. A local administrator with\nCAP_SYS_ADMIN can crash the kernel this way without ever starting the\nserver.\n\nnn->nfsd_serv is set when the service is created, which precedes\ntable allocation. NFSD_NET_UP instead brackets the window where the\ntables are live: set at the end of nfsd_startup_net() and cleared in\nnfsd_shutdown_net() after they are freed, both under nfsd_mutex.\nGating the three unlock paths on NFSD_NET_UP fixes the startup-time\nNULL dereference while preserving the earlier post-shutdown\nuse-after-free fix."}], "affected": [{"product": "Linux", "vendor": "Linux", "defaultStatus": "unaffected", "repo": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git", "programFiles": ["fs/nfsd/nfs4proc.c", "fs/nfsd/nfs4state.c", "fs/nfsd/nfsctl.c"], "versions": [{"version": "1ac3629bf012592cb0320e52a1cceb319a05ad17", "lessThan": "73bf459d696ecf207a9037bf9bb70c51a459469e", "status": "affected", "versionType": "git"}, {"version": "1ac3629bf012592cb0320e52a1cceb319a05ad17", "lessThan": "104a51265042b4424085741c963cb858ac29ec0b", "status": "affected", "versionType": "git"}, {"version": "1ac3629bf012592cb0320e52a1cceb319a05ad17", "lessThan": "0146467a2fce845cb6629979c3e9c58dd3d3a6a3", "status": "affected", "versionType": "git"}, {"version": "1ac3629bf012592cb0320e52a1cceb319a05ad17", "lessThan": "2f3e6638aebc0ab8afb8b4e9816ea9a1cad85378", "status": "affected", "versionType": "git"}]}, {"product": "Linux", "vendor": "Linux", "defaultStatus": "affected", "repo": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git", "programFiles": ["fs/nfsd/nfs4proc.c", "fs/nfsd/nfs4state.c", "fs/nfsd/nfsctl.c"], "versions": [{"version": "6.9", "status": "affected"}, {"version": "0", "lessThan": "6.9", "status": "unaffected", "versionType": "semver"}, {"version": "6.12.111", "lessThanOrEqual": "6.12.*", "status": "unaffected", "versionType": "semver"}, {"version": "6.18.51", "lessThanOrEqual": "6.18.*", "status": "unaffected", "versionType": "semver"}, {"version": "7.2.5", "lessThanOrEqual": "7.2.*", "status": "unaffected", "versionType": "semver"}, {"version": "7.3", "lessThanOrEqual": "*", "status": "unaffected", "versionType": "original_commit_for_fix"}]}], "cpeApplicability": [{"nodes": [{"operator": "OR", "negate": false, "cpeMatch": [{"vulnerable": true, "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*", "versionStartIncluding": "6.9", "versionEndExcluding": "6.12.111"}, {"vulnerable": true, "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*", "versionStartIncluding": "6.9", "versionEndExcluding": "6.18.51"}, {"vulnerable": true, "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*", "versionStartIncluding": "6.9", "versionEndExcluding": "7.2.5"}, {"vulnerable": true, "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*", "versionStartIncluding": "6.9", "versionEndExcluding": "7.3"}]}]}], "references": [{"url": "https://git.kernel.org/stable/c/73bf459d696ecf207a9037bf9bb70c51a459469e"}, {"url": "https://git.kernel.org/stable/c/104a51265042b4424085741c963cb858ac29ec0b"}, {"url": "https://git.kernel.org/stable/c/0146467a2fce845cb6629979c3e9c58dd3d3a6a3"}, {"url": "https://git.kernel.org/stable/c/2f3e6638aebc0ab8afb8b4e9816ea9a1cad85378"}], "title": "NFSD: Guard admin state-revocation walks with NFSD_NET_UP", "x_generator": {"engine": "bippy-1.2.0"}}}}

{}

{"affected": [{"affectedData": [{"defaultStatus": "unaffected", "product": "Linux", "programFiles": ["fs/nfsd/nfs4proc.c", "fs/nfsd/nfs4state.c", "fs/nfsd/nfsctl.c"], "repo": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git", "vendor": "Linux", "versions": [{"lessThan": "73bf459d696ecf207a9037bf9bb70c51a459469e", "status": "affected", "version": "1ac3629bf012592cb0320e52a1cceb319a05ad17", "versionType": "git"}, {"lessThan": "104a51265042b4424085741c963cb858ac29ec0b", "status": "affected", "version": "1ac3629bf012592cb0320e52a1cceb319a05ad17", "versionType": "git"}, {"lessThan": "0146467a2fce845cb6629979c3e9c58dd3d3a6a3", "status": "affected", "version": "1ac3629bf012592cb0320e52a1cceb319a05ad17", "versionType": "git"}, {"lessThan": "2f3e6638aebc0ab8afb8b4e9816ea9a1cad85378", "status": "affected", "version": "1ac3629bf012592cb0320e52a1cceb319a05ad17", "versionType": "git"}]}, {"defaultStatus": "affected", "product": "Linux", "programFiles": ["fs/nfsd/nfs4proc.c", "fs/nfsd/nfs4state.c", "fs/nfsd/nfsctl.c"], "repo": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git", "vendor": "Linux", "versions": [{"status": "affected", "version": "6.9"}, {"lessThan": "6.9", "status": "unaffected", "version": "0", "versionType": "semver"}, {"lessThanOrEqual": "6.12.*", "status": "unaffected", "version": "6.12.111", "versionType": "semver"}, {"lessThanOrEqual": "6.18.*", "status": "unaffected", "version": "6.18.51", "versionType": "semver"}, {"lessThanOrEqual": "7.2.*", "status": "unaffected", "version": "7.2.5", "versionType": "semver"}, {"lessThanOrEqual": "*", "status": "unaffected", "version": "7.3", "versionType": "original_commit_for_fix"}]}], "source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67"}], "cveTags": [], "descriptions": [{"lang": "en", "value": "In the Linux kernel, the following vulnerability has been resolved:\n\nNFSD: Guard admin state-revocation walks with NFSD_NET_UP\n\nWriting to /proc/fs/nfsd/unlock_filesystem, or sending the\nNFSD_CMD_UNLOCK_FILESYSTEM or NFSD_CMD_UNLOCK_EXPORT netlink command,\nwalks the NFSv4 client hash tables to revoke open state and cancel\nasync COPY operations. All three handlers gate that walk on\nnn->nfsd_serv, but a listener added via portlist or netlink\nlistener_set sets nn->nfsd_serv before any nfsd thread starts.\nnfsd_startup_net() has not yet allocated nn->conf_id_hashtbl, so the\nwalkers dereference a NULL table. A local administrator with\nCAP_SYS_ADMIN can crash the kernel this way without ever starting the\nserver.\n\nnn->nfsd_serv is set when the service is created, which precedes\ntable allocation. NFSD_NET_UP instead brackets the window where the\ntables are live: set at the end of nfsd_startup_net() and cleared in\nnfsd_shutdown_net() after they are freed, both under nfsd_mutex.\nGating the three unlock paths on NFSD_NET_UP fixes the startup-time\nNULL dereference while preserving the earlier post-shutdown\nuse-after-free fix."}], "id": "CVE-2026-90039", "lastModified": "2026-10-19T09:18:52.147", "metrics": {}, "published": "2026-09-16T11:17:17.110", "references": [{"source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67", "url": "https://git.kernel.org/stable/c/0146467a2fce845cb6629979c3e9c58dd3d3a6a3"}, {"source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67", "url": "https://git.kernel.org/stable/c/104a51265042b4424085741c963cb858ac29ec0b"}, {"source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67", "url": "https://git.kernel.org/stable/c/2f3e6638aebc0ab8afb8b4e9816ea9a1cad85378"}, {"source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67", "url": "https://git.kernel.org/stable/c/73bf459d696ecf207a9037bf9bb70c51a459469e"}], "sourceIdentifier": "416baaa9-dc9f-4396-8d5f-8c081fb06d67", "vulnStatus": "Received"}

{}

{"affected": [{"configurations": [{"platform": null, "status": "affected", "versions": {"scheme": "code_commit", "value": "[1ac3629bf012592cb0320e52a1cceb319a05ad17,104a51265042b4424085741c963cb858ac29ec0b)"}}, {"platform": null, "status": "affected", "versions": {"scheme": "code_commit", "value": "[1ac3629bf012592cb0320e52a1cceb319a05ad17,0146467a2fce845cb6629979c3e9c58dd3d3a6a3)"}}, {"platform": null, "status": "affected", "versions": {"scheme": "code_commit", "value": "[1ac3629bf012592cb0320e52a1cceb319a05ad17,2f3e6638aebc0ab8afb8b4e9816ea9a1cad85378)"}}], "enrichment": {"confidence": 99.0, "confidence_source": "inferred", "scores": [{"score": 99.0, "source": "inferred"}, {"score": 100.0, "source": "matching"}]}, "original": {"product": "Linux", "source": "cna", "vendor": "Linux"}, "product": "linux_kernel", "vendor": "linux"}, {"configurations": [{"platform": null, "status": "affected", "versions": {"scheme": "generic", "value": "6.9"}}, {"platform": null, "status": "unaffected", "versions": {"scheme": "generic", "value": "[0,6.9)"}}, {"platform": null, "status": "unaffected", "versions": {"scheme": "semver", "value": "[6.18.51,6.19.0)"}}, {"platform": null, "status": "unaffected", "versions": {"scheme": "semver", "value": "[7.2.5,7.3.0)"}}, {"platform": null, "status": "unaffected", "versions": {"scheme": "generic", "value": "[7.3-rc1,*]"}}], "enrichment": {"confidence": 99.0, "confidence_source": "inferred", "scores": [{"score": 99.0, "source": "inferred"}, {"score": 100.0, "source": "matching"}]}, "original": {"product": "Linux", "source": "cna", "vendor": "Linux"}, "product": "linux_kernel", "vendor": "linux"}], "created": "2026-09-17T16:15:14.933972+00:00", "updated": "2026-09-18T04:30:03.557108+00:00", "vendors": ["linux", "linux$PRODUCT$linux_kernel"], "weaknesses": ["CWE-476"]}