CVE-2026-53395

{"dataType": "CVE_RECORD", "dataVersion": "5.2", "cveMetadata": {"cveId": "CVE-2026-53395", "assignerOrgId": "416baaa9-dc9f-4396-8d5f-8c081fb06d67", "state": "PUBLISHED", "assignerShortName": "Linux", "dateReserved": "2026-06-09T07:44:35.402Z", "datePublished": "2026-07-19T12:01:57.816Z", "dateUpdated": "2026-08-17T04:50:47.054Z"}, "containers": {"cna": {"providerMetadata": {"orgId": "416baaa9-dc9f-4396-8d5f-8c081fb06d67", "shortName": "Linux", "dateUpdated": "2026-08-17T04:50:47.054Z"}, "descriptions": [{"lang": "en", "value": "In the Linux kernel, the following vulnerability has been resolved:\n\nnfsd: fix dead ACL conflict guard in nfsd4_create\n\nnfsd4_create() steals create->cr_dpacl/cr_pacl into the local\nnfsd_attrs via the designated initializer, then immediately sets the\nsource pointers to NULL. The subsequent conflict guard tests the\nalready-nilled source fields, making it permanently dead code:\n\n if (create->cr_acl) {\n if (create->cr_dpacl || create->cr_pacl) /* always false */\n\nWhen a client encodes both FATTR4_WORD0_ACL and\nFATTR4_WORD2_POSIX_{DEFAULT,ACCESS}_ACL in the same CREATE fattr\nbitmap, nfsd4_acl_to_attr() overwrites attrs.na_pacl/na_dpacl without\nreleasing the originals, leaking two posix_acl slab objects per\nrequest. Repeated requests cause unbounded slab exhaustion.\n\nFix by checking attrs.na_dpacl/na_pacl (the stolen values) instead of\nthe nilled create->cr_dpacl/cr_pacl, matching the correct pattern\nalready used in nfsd4_setattr()."}], "metrics": [{"cvssV3_1": {"version": "3.1", "vectorString": "CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H", "baseScore": 7.5, "baseSeverity": "HIGH"}, "scenarios": [{"lang": "en", "value": "AV:N - The vulnerability is reached through the in-kernel NFS server (nfsd) processing remotely submitted NFSv4 COMPOUND requests containing OP_CREATE over the network (TCP/2049).\nAC:L - An attacker can reliably trigger the leak by sending CREATE operations with both FATTR4_WORD0_ACL and FATTR4_WORD2_POSIX_DEFAULT/ACCESS_ACL set in the fattr bitmap; no race or uncontrollable conditions are required.\nPR:N - Exploitation requires only network reachability to nfsd and standard NFSv4 client authentication to an export; no elevated Linux privileges on the server are needed beyond being an authorized NFS client.\nUI:N - The leak is triggered entirely by crafted NFS protocol requests with no action required from a human user on the server.\nS:U - Impact is confined to kernel memory exhaustion on the NFS server; it does not cross a security boundary such as a VM or sandbox escape.\nC:N - The bug causes reference leaks of posix_acl slab objects only; there is no out-of-bounds access, use-after-free, or other memory corruption that could disclose data.\nI:N - No data modification or memory corruption occurs; the only effect is unreleased kernel heap allocations.\nA:H - Each malicious CREATE leaks two posix_acl slab objects, and repeated requests cause unbounded slab exhaustion that can render the NFS server and potentially the entire host unavailable through OOM conditions."}]}], "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"], "versions": [{"version": "d2ca50606f5f0235d7780c1cd73b6614a5d07620", "lessThan": "8371cc5c0a2cc2a71b3dcfd47ff1f7fcfc526a5e", "status": "affected", "versionType": "git"}, {"version": "d2ca50606f5f0235d7780c1cd73b6614a5d07620", "lessThan": "a60f25a800846ab8e5a13f8a9d05111f2aee55a7", "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"], "versions": [{"version": "7.0", "status": "affected"}, {"version": "0", "lessThan": "7.0", "status": "unaffected", "versionType": "semver"}, {"version": "7.1.3", "lessThanOrEqual": "7.1.*", "status": "unaffected", "versionType": "semver"}, {"version": "7.2", "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": "7.0", "versionEndExcluding": "7.1.3"}, {"vulnerable": true, "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*", "versionStartIncluding": "7.0", "versionEndExcluding": "7.2"}]}]}], "references": [{"url": "https://git.kernel.org/stable/c/8371cc5c0a2cc2a71b3dcfd47ff1f7fcfc526a5e"}, {"url": "https://git.kernel.org/stable/c/a60f25a800846ab8e5a13f8a9d05111f2aee55a7"}], "title": "nfsd: fix dead ACL conflict guard in nfsd4_create", "x_generator": {"engine": "bippy-1.2.0"}}}}

{}

{"affected": [{"affectedData": [{"defaultStatus": "unaffected", "product": "Linux", "programFiles": ["fs/nfsd/nfs4proc.c"], "repo": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git", "vendor": "Linux", "versions": [{"lessThan": "8371cc5c0a2cc2a71b3dcfd47ff1f7fcfc526a5e", "status": "affected", "version": "d2ca50606f5f0235d7780c1cd73b6614a5d07620", "versionType": "git"}, {"lessThan": "a60f25a800846ab8e5a13f8a9d05111f2aee55a7", "status": "affected", "version": "d2ca50606f5f0235d7780c1cd73b6614a5d07620", "versionType": "git"}]}, {"defaultStatus": "affected", "product": "Linux", "programFiles": ["fs/nfsd/nfs4proc.c"], "repo": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git", "vendor": "Linux", "versions": [{"status": "affected", "version": "7.0"}, {"lessThan": "7.0", "status": "unaffected", "version": "0", "versionType": "semver"}, {"lessThanOrEqual": "7.1.*", "status": "unaffected", "version": "7.1.3", "versionType": "semver"}, {"lessThanOrEqual": "*", "status": "unaffected", "version": "7.2", "versionType": "original_commit_for_fix"}]}], "source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67"}], "configurations": [{"nodes": [{"cpeMatch": [{"criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*", "matchCriteriaId": "63CFDFF9-82B8-4490-8239-D88ABC42DF23", "versionEndExcluding": "7.1.3", "versionStartIncluding": "7.0", "vulnerable": true}], "negate": false, "operator": "OR"}]}], "cveTags": [], "descriptions": [{"lang": "en", "value": "In the Linux kernel, the following vulnerability has been resolved:\n\nnfsd: fix dead ACL conflict guard in nfsd4_create\n\nnfsd4_create() steals create->cr_dpacl/cr_pacl into the local\nnfsd_attrs via the designated initializer, then immediately sets the\nsource pointers to NULL. The subsequent conflict guard tests the\nalready-nilled source fields, making it permanently dead code:\n\n if (create->cr_acl) {\n if (create->cr_dpacl || create->cr_pacl) /* always false */\n\nWhen a client encodes both FATTR4_WORD0_ACL and\nFATTR4_WORD2_POSIX_{DEFAULT,ACCESS}_ACL in the same CREATE fattr\nbitmap, nfsd4_acl_to_attr() overwrites attrs.na_pacl/na_dpacl without\nreleasing the originals, leaking two posix_acl slab objects per\nrequest. Repeated requests cause unbounded slab exhaustion.\n\nFix by checking attrs.na_dpacl/na_pacl (the stolen values) instead of\nthe nilled create->cr_dpacl/cr_pacl, matching the correct pattern\nalready used in nfsd4_setattr()."}], "id": "CVE-2026-53395", "lastModified": "2026-08-17T05:17:14.033", "metrics": {"cvssMetricV31": [{"cvssData": {"attackComplexity": "LOW", "attackVector": "NETWORK", "availabilityImpact": "HIGH", "baseScore": 7.5, "baseSeverity": "HIGH", "confidentialityImpact": "NONE", "integrityImpact": "NONE", "privilegesRequired": "NONE", "scope": "UNCHANGED", "userInteraction": "NONE", "vectorString": "CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H", "version": "3.1"}, "exploitabilityScore": 3.9, "impactScore": 3.6, "source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67", "type": "Secondary"}]}, "published": "2026-07-19T12:16:50.597", "references": [{"source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67", "tags": ["Patch"], "url": "https://git.kernel.org/stable/c/8371cc5c0a2cc2a71b3dcfd47ff1f7fcfc526a5e"}, {"source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67", "tags": ["Patch"], "url": "https://git.kernel.org/stable/c/a60f25a800846ab8e5a13f8a9d05111f2aee55a7"}], "sourceIdentifier": "416baaa9-dc9f-4396-8d5f-8c081fb06d67", "vulnStatus": "Analyzed", "weaknesses": [{"description": [{"lang": "en", "value": "CWE-674"}], "source": "nvd@nist.gov", "type": "Primary"}]}

{"bugzilla": {"description": "kernel: nfsd: fix dead ACL conflict guard in nfsd4_create", "id": "2502209", "url": "https://bugzilla.redhat.com/show_bug.cgi?id=2502209"}, "csaw": false, "cvss3": {"cvss3_base_score": "7.0", "cvss3_scoring_vector": "CVSS:3.1/AV:L/AC:H/PR:L/UI:N/S:U/C:H/I:H/A:H", "status": "draft"}, "cwe": "CWE-772", "details": ["In the Linux kernel, the following vulnerability has been resolved:\nnfsd: fix dead ACL conflict guard in nfsd4_create\nnfsd4_create() steals create->cr_dpacl/cr_pacl into the local\nnfsd_attrs via the designated initializer, then immediately sets the\nsource pointers to NULL. The subsequent conflict guard tests the\nalready-nilled source fields, making it permanently dead code:\nif (create->cr_acl) {\nif (create->cr_dpacl || create->cr_pacl) /* always false */\nWhen a client encodes both FATTR4_WORD0_ACL and\nFATTR4_WORD2_POSIX_{DEFAULT,ACCESS}_ACL in the same CREATE fattr\nbitmap, nfsd4_acl_to_attr() overwrites attrs.na_pacl/na_dpacl without\nreleasing the originals, leaking two posix_acl slab objects per\nrequest. Repeated requests cause unbounded slab exhaustion.\nFix by checking attrs.na_dpacl/na_pacl (the stolen values) instead of\nthe nilled create->cr_dpacl/cr_pacl, matching the correct pattern\nalready used in nfsd4_setattr().", "A flaw was found in the Linux kernel's Network File System (NFS) daemon (nfsd). A remote attacker can exploit this vulnerability by sending specially crafted NFS CREATE requests that include conflicting Access Control List (ACL) attributes. This leads to a memory leak, where the system fails to release memory objects, causing unbounded memory exhaustion. Repeated exploitation can result in a Denial of Service (DoS), making the system unresponsive to legitimate requests."], "name": "CVE-2026-53395", "package_state": [{"cpe": "cpe:/o:redhat:enterprise_linux:10", "fix_state": "Affected", "package_name": "kernel", "product_name": "Red Hat Enterprise Linux 10"}, {"cpe": "cpe:/o:redhat:enterprise_linux:6", "fix_state": "Out of support scope", "package_name": "kernel", "product_name": "Red Hat Enterprise Linux 6"}, {"cpe": "cpe:/o:redhat:enterprise_linux:7", "fix_state": "Not affected", "package_name": "kernel", "product_name": "Red Hat Enterprise Linux 7"}, {"cpe": "cpe:/o:redhat:enterprise_linux:7", "fix_state": "Not affected", "package_name": "kernel-rt", "product_name": "Red Hat Enterprise Linux 7"}, {"cpe": "cpe:/o:redhat:enterprise_linux:8", "fix_state": "Not affected", "package_name": "kernel", "product_name": "Red Hat Enterprise Linux 8"}, {"cpe": "cpe:/o:redhat:enterprise_linux:8", "fix_state": "Not affected", "package_name": "kernel-rt", "product_name": "Red Hat Enterprise Linux 8"}, {"cpe": "cpe:/o:redhat:enterprise_linux:9", "fix_state": "Not affected", "package_name": "kernel", "product_name": "Red Hat Enterprise Linux 9"}, {"cpe": "cpe:/o:redhat:enterprise_linux:9", "fix_state": "Not affected", "package_name": "kernel-rt", "product_name": "Red Hat Enterprise Linux 9"}], "public_date": "2026-07-19T00:00:00Z", "references": ["https://www.cve.org/CVERecord?id=CVE-2026-53395\nhttps://nvd.nist.gov/vuln/detail/CVE-2026-53395\nhttps://lore.kernel.org/linux-cve-announce/2026071957-CVE-2026-53395-a139@gregkh/T"], "threat_severity": "Moderate"}

{"affected": [{"configurations": [{"platform": null, "status": "affected", "versions": {"scheme": "code_commit", "value": "[d2ca50606f5f0235d7780c1cd73b6614a5d07620,8371cc5c0a2cc2a71b3dcfd47ff1f7fcfc526a5e)"}}, {"platform": null, "status": "affected", "versions": {"scheme": "code_commit", "value": "[d2ca50606f5f0235d7780c1cd73b6614a5d07620,a60f25a800846ab8e5a13f8a9d05111f2aee55a7)"}}], "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": "7.0"}}, {"platform": null, "status": "unaffected", "versions": {"scheme": "generic", "value": "[0,7.0)"}}, {"platform": null, "status": "unaffected", "versions": {"scheme": "semver", "value": "[7.1.3,8.0.0)"}}, {"platform": null, "status": "unaffected", "versions": {"scheme": "generic", "value": "[7.2-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": "2026-07-22T00:30:04.488413+00:00", "updated": "2026-08-13T12:15:17.541191+00:00", "vendors": ["linux", "linux$PRODUCT$linux_kernel"]}