CVE-2026-89671
Full vulnerability record from the local CVENow database.
Description
In the Linux kernel, the following vulnerability has been resolved: nfsd: gate nfs3 setacl by argp->mask nfsd3_proc_setacl() calls set_posix_acl() unconditionally for both ACL_TYPE_ACCESS and ACL_TYPE_DEFAULT, passing argp->acl_access and argp->acl_default verbatim. The NFSv3 ACL decoder only populates those pointers when the corresponding mask bit is set: nfs3svc_decode_setaclargs() if (args->mask & NFS_ACL) decode into acl_access if (args->mask & NFS_DFACL) decode into acl_default /* otherwise the pointer stays NULL (pc_argzero) */ nfsd3_proc_setacl() set_posix_acl(.., ACL_TYPE_ACCESS, argp->acl_access) set_posix_acl(.., ACL_TYPE_DEFAULT, argp->acl_default) set_posix_acl(idmap, dentry, type, NULL) is the VFS "remove this ACL type" operation. A NULL pointer that means "the client did not send this arm" is therefore indistinguishable from "the client asked to remove this ACL". A SETACL with mask=NFS_ACL silently drops the directory's default ACL; mask=0 drops both. The sibling nfsd3_proc_getacl() already consults argp->mask before touching each arm; mirror that in setacl. Fix by wrapping each set_posix_acl() call in the matching mask bit check and initializing error to 0 before inode_lock so that a request with neither bit set leaves the on-disk ACLs untouched and returns nfs_ok. The out_drop_lock path and the unconditional posix_acl_release() at out: are preserved; both NULL-tolerate the skipped arms.
View original CVE JSON
{
"id": "CVE-2026-89671",
"sourceIdentifier": "416baaa9-dc9f-4396-8d5f-8c081fb06d67",
"published": "2026-09-11T20:19:53.647",
"lastModified": "2026-10-30T13:20:25.420",
"vulnStatus": "Received",
"cveTags": [],
"descriptions": [
{
"lang": "en",
"value": "In the Linux kernel, the following vulnerability has been resolved:\n\nnfsd: gate nfs3 setacl by argp->mask\n\nnfsd3_proc_setacl() calls set_posix_acl() unconditionally for both\nACL_TYPE_ACCESS and ACL_TYPE_DEFAULT, passing argp->acl_access and\nargp->acl_default verbatim. The NFSv3 ACL decoder only populates\nthose pointers when the corresponding mask bit is set:\n\n nfs3svc_decode_setaclargs()\n if (args->mask & NFS_ACL) decode into acl_access\n if (args->mask & NFS_DFACL) decode into acl_default\n /* otherwise the pointer stays NULL (pc_argzero) */\n\n nfsd3_proc_setacl()\n set_posix_acl(.., ACL_TYPE_ACCESS, argp->acl_access)\n set_posix_acl(.., ACL_TYPE_DEFAULT, argp->acl_default)\n\nset_posix_acl(idmap, dentry, type, NULL) is the VFS \"remove this\nACL type\" operation. A NULL pointer that means \"the client did not\nsend this arm\" is therefore indistinguishable from \"the client\nasked to remove this ACL\". A SETACL with mask=NFS_ACL silently\ndrops the directory's default ACL; mask=0 drops both.\n\nThe sibling nfsd3_proc_getacl() already consults argp->mask before\ntouching each arm; mirror that in setacl.\n\nFix by wrapping each set_posix_acl() call in the matching mask bit\ncheck and initializing error to 0 before inode_lock so that a\nrequest with neither bit set leaves the on-disk ACLs untouched and\nreturns nfs_ok. The out_drop_lock path and the unconditional\nposix_acl_release() at out: are preserved; both NULL-tolerate the\nskipped arms."
}
],
"affected": [
{
"source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67",
"affectedData": [
{
"vendor": "Linux",
"product": "Linux",
"defaultStatus": "unaffected",
"programFiles": [
"fs/nfsd/nfs3acl.c"
],
"repo": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git",
"versions": [
{
"version": "a257cdd0e2179630d3201c32ba14d7fcb3c3a055",
"lessThan": "beeb33152873ad40692bd255b562966f8ba43dbd",
"versionType": "git",
"status": "affected"
},
{
"version": "a257cdd0e2179630d3201c32ba14d7fcb3c3a055",
"lessThan": "3be1d8611dae4829e4608007db29f4a8748c37b2",
"versionType": "git",
"status": "affected"
},
{
"version": "a257cdd0e2179630d3201c32ba14d7fcb3c3a055",
"lessThan": "68a80b26efdff1d09f8ae1773c6a915abb9e191d",
"versionType": "git",
"status": "affected"
},
{
"version": "a257cdd0e2179630d3201c32ba14d7fcb3c3a055",
"lessThan": "b3bff820d068ea59767d4e91a3258231a879da5f",
"versionType": "git",
"status": "affected"
},
{
"version": "a257cdd0e2179630d3201c32ba14d7fcb3c3a055",
"lessThan": "ff99ed007f065198fd723152405c22aa558f700b",
"versionType": "git",
"status": "affected"
},
{
"version": "a257cdd0e2179630d3201c32ba14d7fcb3c3a055",
"lessThan": "453d7198a0ab07a12d46e0575861ac7b932da17e",
"versionType": "git",
"status": "affected"
}
]
},
{
"vendor": "Linux",
"product": "Linux",
"defaultStatus": "affected",
"programFiles": [
"fs/nfsd/nfs3acl.c"
],
"repo": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git",
"versions": [
{
"version": "2.6.13",
"status": "affected"
},
{
"version": "0",
"lessThan": "2.6.13",
"versionType": "semver",
"status": "unaffected"
},
{
"version": "6.1.191",
"lessThanOrEqual": "6.1.*",
"versionType": "semver",
"status": "unaffected"
},
{
"version": "6.6.157",
"lessThanOrEqual": "6.6.*",
"versionType": "semver",
"status": "unaffected"
},
{
"version": "6.12.109",
"lessThanOrEqual": "6.12.*",
"versionType": "semver",
"status": "unaffected"
},
{
"version": "6.18.50",
"lessThanOrEqual": "6.18.*",
"versionType": "semver",
"status": "unaffected"
},
{
"version": "7.2.4",
"lessThanOrEqual": "7.2.*",
"versionType": "semver",
"status": "unaffected"
},
{
"version": "7.3",
"lessThanOrEqual": "*",
"versionType": "original_commit_for_fix",
"status": "unaffected"
}
]
}
]
}
],
"metrics": {
"cvssMetricV31": [
{
"source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67",
"type": "Secondary",
"cvssData": {
"version": "3.1",
"vectorString": "CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:N",
"baseScore": 9.1,
"baseSeverity": "CRITICAL",
"attackVector": "NETWORK",
"attackComplexity": "LOW",
"privilegesRequired": "NONE",
"userInteraction": "NONE",
"scope": "UNCHANGED",
"confidentialityImpact": "HIGH",
"integrityImpact": "HIGH",
"availabilityImpact": "NONE"
},
"exploitabilityScore": 3.9,
"impactScore": 5.2
}
],
"ssvcV203": [
{
"source": "134c704f-9b21-4f2e-91b3-4a467353bcc0",
"ssvcData": {
"timestamp": "2026-10-16T19:25:43.543380Z",
"id": "CVE-2026-89671",
"options": [
{
"exploitation": "none"
},
{
"automatable": "yes"
},
{
"technicalImpact": "total"
}
],
"role": "CISA Coordinator",
"version": "2.0.3"
}
}
]
},
"references": [
{
"url": "https://git.kernel.org/stable/c/3be1d8611dae4829e4608007db29f4a8748c37b2",
"source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67"
},
{
"url": "https://git.kernel.org/stable/c/453d7198a0ab07a12d46e0575861ac7b932da17e",
"source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67"
},
{
"url": "https://git.kernel.org/stable/c/68a80b26efdff1d09f8ae1773c6a915abb9e191d",
"source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67"
},
{
"url": "https://git.kernel.org/stable/c/b3bff820d068ea59767d4e91a3258231a879da5f",
"source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67"
},
{
"url": "https://git.kernel.org/stable/c/beeb33152873ad40692bd255b562966f8ba43dbd",
"source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67"
},
{
"url": "https://git.kernel.org/stable/c/ff99ed007f065198fd723152405c22aa558f700b",
"source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67"
}
]
}