{"dataType": "CVE_RECORD", "dataVersion": "5.2", "cveMetadata": {"cveId": "CVE-2026-89659", "assignerOrgId": "416baaa9-dc9f-4396-8d5f-8c081fb06d67", "state": "PUBLISHED", "assignerShortName": "Linux", "dateReserved": "2026-09-11T19:38:34.744Z", "datePublished": "2026-09-11T19:45:47.587Z", "dateUpdated": "2026-09-11T19:45:47.587Z"}, "containers": {"cna": {"providerMetadata": {"orgId": "416baaa9-dc9f-4396-8d5f-8c081fb06d67", "shortName": "Linux", "dateUpdated": "2026-09-11T19:45:47.587Z"}, "descriptions": [{"lang": "en", "value": "In the Linux kernel, the following vulnerability has been resolved:\n\nNFSD: Prevent client use-after-free during delegation revoke\n\nA delegation stateid holds only a bare pointer to its owning\nnfs4_client and does not keep it alive. The client survives its\nstateids only because __destroy_client() drains cl_delegations and\ncl_revoked before free_client() runs.\n\nnfs4_laundromat() breaks that invariant: it unhashes an\nexpired delegation from cl_delegations, drops deleg_lock, then\nrevoke_delegation() relinks it onto cl_revoked under cl_lock. In that\nwindow the delegation is on neither list, so client_has_state() can\nreport no remaining state.\n\nEvery teardown path first requires cl_rpc_users to be zero, but\nthe laundromat holds no such reference. A client whose recalled\ndelegation has just timed out can therefore reach free_client()\nwhile revoke_delegation() is still about to dereference cl_lock,\na use-after-free.\n\nPin the client with cl_rpc_users across the revoke so teardown blocks\nuntil it completes, then reap the delegation from cl_revoked. A client\nalready expiring reaps its own, so skip it and leave the delegation on\ndel_recall_lru."}], "affected": [{"product": "Linux", "vendor": "Linux", "defaultStatus": "unaffected", "repo": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git", "programFiles": ["fs/nfsd/netns.h", "fs/nfsd/nfs4state.c"], "versions": [{"version": "3bd64a5ba1719c2bb6cba4493dfd3e23a7653e54", "lessThan": "3c0a53ee0b442348d8d2286d6960d3f07bb3a3d3", "status": "affected", "versionType": "git"}, {"version": "3bd64a5ba1719c2bb6cba4493dfd3e23a7653e54", "lessThan": "2a9d637c2a8fd8ac29ad9b29f28d122ef75c1a56", "status": "affected", "versionType": "git"}, {"version": "3bd64a5ba1719c2bb6cba4493dfd3e23a7653e54", "lessThan": "4683ca76b3b7e5808338491c6eb3c20e6b4894d5", "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/netns.h", "fs/nfsd/nfs4state.c"], "versions": [{"version": "3.10", "status": "affected"}, {"version": "0", "lessThan": "3.10", "status": "unaffected", "versionType": "semver"}, {"version": "6.18.51", "lessThanOrEqual": "6.18.*", "status": "unaffected", "versionType": "semver"}, {"version": "7.2.4", "lessThanOrEqual": "7.2.*", "status": "unaffected", "versionType": "semver"}, {"version": "7.3-rc1", "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": "3.10", "versionEndExcluding": "6.18.51"}, {"vulnerable": true, "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*", "versionStartIncluding": "3.10", "versionEndExcluding": "7.2.4"}, {"vulnerable": true, "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*", "versionStartIncluding": "3.10", "versionEndExcluding": "7.3-rc1"}]}]}], "references": [{"url": "https://git.kernel.org/stable/c/3c0a53ee0b442348d8d2286d6960d3f07bb3a3d3"}, {"url": "https://git.kernel.org/stable/c/2a9d637c2a8fd8ac29ad9b29f28d122ef75c1a56"}, {"url": "https://git.kernel.org/stable/c/4683ca76b3b7e5808338491c6eb3c20e6b4894d5"}], "title": "NFSD: Prevent client use-after-free during delegation revoke", "x_generator": {"engine": "bippy-1.2.0"}}}}

{}

{"affected": [{"affectedData": [{"defaultStatus": "unaffected", "product": "Linux", "programFiles": ["fs/nfsd/netns.h", "fs/nfsd/nfs4state.c"], "repo": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git", "vendor": "Linux", "versions": [{"lessThan": "3c0a53ee0b442348d8d2286d6960d3f07bb3a3d3", "status": "affected", "version": "3bd64a5ba1719c2bb6cba4493dfd3e23a7653e54", "versionType": "git"}, {"lessThan": "2a9d637c2a8fd8ac29ad9b29f28d122ef75c1a56", "status": "affected", "version": "3bd64a5ba1719c2bb6cba4493dfd3e23a7653e54", "versionType": "git"}, {"lessThan": "4683ca76b3b7e5808338491c6eb3c20e6b4894d5", "status": "affected", "version": "3bd64a5ba1719c2bb6cba4493dfd3e23a7653e54", "versionType": "git"}]}, {"defaultStatus": "affected", "product": "Linux", "programFiles": ["fs/nfsd/netns.h", "fs/nfsd/nfs4state.c"], "repo": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git", "vendor": "Linux", "versions": [{"status": "affected", "version": "3.10"}, {"lessThan": "3.10", "status": "unaffected", "version": "0", "versionType": "semver"}, {"lessThanOrEqual": "6.18.*", "status": "unaffected", "version": "6.18.51", "versionType": "semver"}, {"lessThanOrEqual": "7.2.*", "status": "unaffected", "version": "7.2.4", "versionType": "semver"}, {"lessThanOrEqual": "*", "status": "unaffected", "version": "7.3-rc1", "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: Prevent client use-after-free during delegation revoke\n\nA delegation stateid holds only a bare pointer to its owning\nnfs4_client and does not keep it alive. The client survives its\nstateids only because __destroy_client() drains cl_delegations and\ncl_revoked before free_client() runs.\n\nnfs4_laundromat() breaks that invariant: it unhashes an\nexpired delegation from cl_delegations, drops deleg_lock, then\nrevoke_delegation() relinks it onto cl_revoked under cl_lock. In that\nwindow the delegation is on neither list, so client_has_state() can\nreport no remaining state.\n\nEvery teardown path first requires cl_rpc_users to be zero, but\nthe laundromat holds no such reference. A client whose recalled\ndelegation has just timed out can therefore reach free_client()\nwhile revoke_delegation() is still about to dereference cl_lock,\na use-after-free.\n\nPin the client with cl_rpc_users across the revoke so teardown blocks\nuntil it completes, then reap the delegation from cl_revoked. A client\nalready expiring reaps its own, so skip it and leave the delegation on\ndel_recall_lru."}], "id": "CVE-2026-89659", "lastModified": "2026-09-11T20:19:52.180", "metrics": {}, "published": "2026-09-11T20:19:52.180", "references": [{"source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67", "url": "https://git.kernel.org/stable/c/2a9d637c2a8fd8ac29ad9b29f28d122ef75c1a56"}, {"source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67", "url": "https://git.kernel.org/stable/c/3c0a53ee0b442348d8d2286d6960d3f07bb3a3d3"}, {"source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67", "url": "https://git.kernel.org/stable/c/4683ca76b3b7e5808338491c6eb3c20e6b4894d5"}], "sourceIdentifier": "416baaa9-dc9f-4396-8d5f-8c081fb06d67", "vulnStatus": "Received"}

{"bugzilla": {"description": "kernel: Linux Kernel: NFSD use-after-free during delegation revoke", "id": "2532119", "url": "https://bugzilla.redhat.com/show_bug.cgi?id=2532119"}, "csaw": false, "cvss3": {"cvss3_base_score": "6.4", "cvss3_scoring_vector": "CVSS:3.1/AV:N/AC:H/PR:L/UI:N/S:U/C:L/I:L/A:H", "status": "draft"}, "cwe": "CWE-825", "details": ["A flaw was found in the Linux kernel's Network File System Daemon (NFSD). This use-after-free vulnerability occurs during the delegation revoke process. When an expired delegation is unhashed, a timing window exists where the client can be prematurely freed before the revocation is complete. This can lead to a system crash or potentially allow an attacker to execute arbitrary code or disclose sensitive information."], "name": "CVE-2026-89659", "public_date": "2026-09-11T19:45:47Z", "references": ["https://www.cve.org/CVERecord?id=CVE-2026-89659\nhttps://nvd.nist.gov/vuln/detail/CVE-2026-89659\nhttps://git.kernel.org/stable/c/2a9d637c2a8fd8ac29ad9b29f28d122ef75c1a56\nhttps://git.kernel.org/stable/c/3c0a53ee0b442348d8d2286d6960d3f07bb3a3d3\nhttps://git.kernel.org/stable/c/4683ca76b3b7e5808338491c6eb3c20e6b4894d5"], "threat_severity": "Important"}

{"created": "2026-09-12T06:15:04.246794+00:00", "updated": "2026-09-12T21:00:13.615867+00:00", "vendors": []}