CVE-2026-64298

{"dataType": "CVE_RECORD", "dataVersion": "5.2", "cveMetadata": {"cveId": "CVE-2026-64298", "assignerOrgId": "416baaa9-dc9f-4396-8d5f-8c081fb06d67", "state": "PUBLISHED", "assignerShortName": "Linux", "dateReserved": "2026-07-19T15:36:31.778Z", "datePublished": "2026-07-25T08:49:35.101Z", "dateUpdated": "2026-10-19T20:38:22.558Z"}, "containers": {"cna": {"providerMetadata": {"orgId": "416baaa9-dc9f-4396-8d5f-8c081fb06d67", "shortName": "Linux", "dateUpdated": "2026-08-17T04:52:55.989Z"}, "descriptions": [{"lang": "en", "value": "In the Linux kernel, the following vulnerability has been resolved:\n\nNFSv4: include MAY_WRITE in open permission mask for O_TRUNC\n\nPOSIX requires write permission to truncate a file, so an open() that\nspecifies O_TRUNC must be authorized for write access regardless of the\nO_ACCMODE access mode.\n\nnfs_open_permission_mask() builds the access mask passed to\nnfs_may_open(), which is the local authorization gate for OPENs the\nclient serves itself from a cached write delegation via the\ncan_open_delegated() path in nfs4_try_open_cached(). The mask is\nderived from O_ACCMODE alone, so an open(O_RDONLY | O_TRUNC) against a\nfile the caller cannot write requests only MAY_READ and passes the\nlocal check. The OPEN is then satisfied locally and the truncation is\nissued to the server as a SETATTR(size=0) over the delegation stateid,\nwhich the server accepts under standard write-delegation semantics.\nPOSIX requires that this open fail with EACCES.\n\nInclude MAY_WRITE in the mask whenever O_TRUNC is set so the local\ncheck matches the access the server would have enforced."}], "metrics": [{"cvssV3_1": {"version": "3.1", "vectorString": "CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:N/I:H/A:H", "baseScore": 7.1, "baseSeverity": "HIGH"}, "scenarios": [{"lang": "en", "value": "AV:L - An unprivileged local process triggers the flaw through open/openat with O_RDONLY|O_TRUNC on an accessible NFSv4-mounted file. The resulting NFS RPC is outbound and does not make the attack remotely reachable.\nAC:L - Once the client holds a standard cached write delegation, a single deterministic open triggers the unauthorized truncation without a race or timing requirement. Delegations persist and the attacker can repeatedly target files actively written through the same client.\nPR:L - The attacker needs only ordinary local access and read/search permission for the target path; no capability or administrative privilege is required. User namespaces are unnecessary.\nUI:N - The attacker invokes open directly and no contemporaneous action by another user is required.\nS:U - The faulty client-side permission check and modification of the delegated NFS file remain within the NFS filesystem access-control authority.\nC:N - The flaw discloses no kernel or file data beyond content the caller was already authorized to read, and it involves no memory corruption.\nI:H - The attacker can irreversibly truncate the complete contents of a file for which write access was denied, causing total integrity loss of that resource.\nA:H - Truncating critical NFS-hosted executables, configuration, databases, or operational data can completely disable dependent systems or services, and the attack can be repeated against additional delegated files."}]}], "affected": [{"product": "Linux", "vendor": "Linux", "defaultStatus": "unaffected", "repo": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git", "programFiles": ["fs/nfs/dir.c"], "versions": [{"version": "af22f94ae02ab9dd4fd7fe628c8434a59cc293be", "lessThan": "4817c8974315b666e895b7d1bb83cd3664c323b1", "status": "affected", "versionType": "git"}, {"version": "af22f94ae02ab9dd4fd7fe628c8434a59cc293be", "lessThan": "cb148a2762d644bff1894728e8835a9a4b84f9ea", "status": "affected", "versionType": "git"}, {"version": "af22f94ae02ab9dd4fd7fe628c8434a59cc293be", "lessThan": "30fdf4df6c3c00efec947e4ddf97f0fdd4473628", "status": "affected", "versionType": "git"}, {"version": "af22f94ae02ab9dd4fd7fe628c8434a59cc293be", "lessThan": "22c1fd1355ad4ca27aa7f0fa02719122dd92d9de", "status": "affected", "versionType": "git"}, {"version": "af22f94ae02ab9dd4fd7fe628c8434a59cc293be", "lessThan": "6bd7d0a06b53c4e797e1a9cea0d2d41aa1b26230", "status": "affected", "versionType": "git"}, {"version": "af22f94ae02ab9dd4fd7fe628c8434a59cc293be", "lessThan": "a937e92c1d00534b5c2e3e9f4381b7e988180797", "status": "affected", "versionType": "git"}, {"version": "af22f94ae02ab9dd4fd7fe628c8434a59cc293be", "lessThan": "e36501b7d4abdcd6d69a7cb901b2f286b7a3d041", "status": "affected", "versionType": "git"}, {"version": "af22f94ae02ab9dd4fd7fe628c8434a59cc293be", "lessThan": "5140f099ecd8a2f2808b7f7b720ee1bad8468974", "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/nfs/dir.c"], "versions": [{"version": "2.6.24", "status": "affected"}, {"version": "0", "lessThan": "2.6.24", "status": "unaffected", "versionType": "semver"}, {"version": "5.10.261", "lessThanOrEqual": "5.10.*", "status": "unaffected", "versionType": "semver"}, {"version": "5.15.212", "lessThanOrEqual": "5.15.*", "status": "unaffected", "versionType": "semver"}, {"version": "6.1.178", "lessThanOrEqual": "6.1.*", "status": "unaffected", "versionType": "semver"}, {"version": "6.6.145", "lessThanOrEqual": "6.6.*", "status": "unaffected", "versionType": "semver"}, {"version": "6.12.96", "lessThanOrEqual": "6.12.*", "status": "unaffected", "versionType": "semver"}, {"version": "6.18.39", "lessThanOrEqual": "6.18.*", "status": "unaffected", "versionType": "semver"}, {"version": "7.1.4", "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": "2.6.24", "versionEndExcluding": "5.10.261"}, {"vulnerable": true, "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*", "versionStartIncluding": "2.6.24", "versionEndExcluding": "5.15.212"}, {"vulnerable": true, "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*", "versionStartIncluding": "2.6.24", "versionEndExcluding": "6.1.178"}, {"vulnerable": true, "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*", "versionStartIncluding": "2.6.24", "versionEndExcluding": "6.6.145"}, {"vulnerable": true, "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*", "versionStartIncluding": "2.6.24", "versionEndExcluding": "6.12.96"}, {"vulnerable": true, "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*", "versionStartIncluding": "2.6.24", "versionEndExcluding": "6.18.39"}, {"vulnerable": true, "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*", "versionStartIncluding": "2.6.24", "versionEndExcluding": "7.1.4"}, {"vulnerable": true, "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*", "versionStartIncluding": "2.6.24", "versionEndExcluding": "7.2"}]}]}], "references": [{"url": "https://git.kernel.org/stable/c/4817c8974315b666e895b7d1bb83cd3664c323b1"}, {"url": "https://git.kernel.org/stable/c/cb148a2762d644bff1894728e8835a9a4b84f9ea"}, {"url": "https://git.kernel.org/stable/c/30fdf4df6c3c00efec947e4ddf97f0fdd4473628"}, {"url": "https://git.kernel.org/stable/c/22c1fd1355ad4ca27aa7f0fa02719122dd92d9de"}, {"url": "https://git.kernel.org/stable/c/6bd7d0a06b53c4e797e1a9cea0d2d41aa1b26230"}, {"url": "https://git.kernel.org/stable/c/a937e92c1d00534b5c2e3e9f4381b7e988180797"}, {"url": "https://git.kernel.org/stable/c/e36501b7d4abdcd6d69a7cb901b2f286b7a3d041"}, {"url": "https://git.kernel.org/stable/c/5140f099ecd8a2f2808b7f7b720ee1bad8468974"}], "title": "NFSv4: include MAY_WRITE in open permission mask for O_TRUNC", "x_generator": {"engine": "bippy-1.2.0"}}, "adp": [{"metrics": [{"other": {"type": "ssvc", "content": {"id": "CVE-2026-64298", "role": "CISA Coordinator", "options": [{"Exploitation": "none"}, {"Automatable": "no"}, {"Technical Impact": "partial"}], "version": "2.0.3", "timestamp": "2026-10-16T15:38:37.476153Z"}}}], "problemTypes": [{"descriptions": [{"lang": "en", "type": "CWE", "cweId": "CWE-862", "description": "CWE-862 Missing Authorization"}]}], "title": "CISA ADP Vulnrichment", "providerMetadata": {"orgId": "134c704f-9b21-4f2e-91b3-4a467353bcc0", "shortName": "CISA-ADP", "dateUpdated": "2026-10-19T20:38:22.558Z"}}]}}

{"dataType": "CVE_RECORD", "containers": {"adp": [{"title": "CISA ADP Vulnrichment", "metrics": [{"other": {"type": "ssvc", "content": {"id": "CVE-2026-64298", "role": "CISA Coordinator", "options": [{"Exploitation": "none"}, {"Automatable": "no"}, {"Technical Impact": "partial"}], "version": "2.0.3", "timestamp": "2026-10-16T15:38:37.476153Z"}}}], "problemTypes": [{"descriptions": [{"lang": "en", "type": "CWE", "cweId": "CWE-862", "description": "CWE-862 Missing Authorization"}]}], "providerMetadata": {"orgId": "134c704f-9b21-4f2e-91b3-4a467353bcc0", "shortName": "CISA-ADP", "dateUpdated": "2026-10-16T15:38:38.240Z"}}], "cna": {"title": "NFSv4: include MAY_WRITE in open permission mask for O_TRUNC", "metrics": [{"cvssV3_1": {"version": "3.1", "baseScore": 7.1, "baseSeverity": "HIGH", "vectorString": "CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:N/I:H/A:H"}, "scenarios": [{"lang": "en", "value": "AV:L - An unprivileged local process triggers the flaw through open/openat with O_RDONLY|O_TRUNC on an accessible NFSv4-mounted file. The resulting NFS RPC is outbound and does not make the attack remotely reachable.\nAC:L - Once the client holds a standard cached write delegation, a single deterministic open triggers the unauthorized truncation without a race or timing requirement. Delegations persist and the attacker can repeatedly target files actively written through the same client.\nPR:L - The attacker needs only ordinary local access and read/search permission for the target path; no capability or administrative privilege is required. User namespaces are unnecessary.\nUI:N - The attacker invokes open directly and no contemporaneous action by another user is required.\nS:U - The faulty client-side permission check and modification of the delegated NFS file remain within the NFS filesystem access-control authority.\nC:N - The flaw discloses no kernel or file data beyond content the caller was already authorized to read, and it involves no memory corruption.\nI:H - The attacker can irreversibly truncate the complete contents of a file for which write access was denied, causing total integrity loss of that resource.\nA:H - Truncating critical NFS-hosted executables, configuration, databases, or operational data can completely disable dependent systems or services, and the attack can be repeated against additional delegated files."}]}], "affected": [{"repo": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git", "vendor": "Linux", "product": "Linux", "versions": [{"status": "affected", "version": "af22f94ae02ab9dd4fd7fe628c8434a59cc293be", "lessThan": "4817c8974315b666e895b7d1bb83cd3664c323b1", "versionType": "git"}, {"status": "affected", "version": "af22f94ae02ab9dd4fd7fe628c8434a59cc293be", "lessThan": "cb148a2762d644bff1894728e8835a9a4b84f9ea", "versionType": "git"}, {"status": "affected", "version": "af22f94ae02ab9dd4fd7fe628c8434a59cc293be", "lessThan": "30fdf4df6c3c00efec947e4ddf97f0fdd4473628", "versionType": "git"}, {"status": "affected", "version": "af22f94ae02ab9dd4fd7fe628c8434a59cc293be", "lessThan": "22c1fd1355ad4ca27aa7f0fa02719122dd92d9de", "versionType": "git"}, {"status": "affected", "version": "af22f94ae02ab9dd4fd7fe628c8434a59cc293be", "lessThan": "6bd7d0a06b53c4e797e1a9cea0d2d41aa1b26230", "versionType": "git"}, {"status": "affected", "version": "af22f94ae02ab9dd4fd7fe628c8434a59cc293be", "lessThan": "a937e92c1d00534b5c2e3e9f4381b7e988180797", "versionType": "git"}, {"status": "affected", "version": "af22f94ae02ab9dd4fd7fe628c8434a59cc293be", "lessThan": "e36501b7d4abdcd6d69a7cb901b2f286b7a3d041", "versionType": "git"}, {"status": "affected", "version": "af22f94ae02ab9dd4fd7fe628c8434a59cc293be", "lessThan": "5140f099ecd8a2f2808b7f7b720ee1bad8468974", "versionType": "git"}], "programFiles": ["fs/nfs/dir.c"], "defaultStatus": "unaffected"}, {"repo": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git", "vendor": "Linux", "product": "Linux", "versions": [{"status": "affected", "version": "2.6.24"}, {"status": "unaffected", "version": "0", "lessThan": "2.6.24", "versionType": "semver"}, {"status": "unaffected", "version": "5.10.261", "versionType": "semver", "lessThanOrEqual": "5.10.*"}, {"status": "unaffected", "version": "5.15.212", "versionType": "semver", "lessThanOrEqual": "5.15.*"}, {"status": "unaffected", "version": "6.1.178", "versionType": "semver", "lessThanOrEqual": "6.1.*"}, {"status": "unaffected", "version": "6.6.145", "versionType": "semver", "lessThanOrEqual": "6.6.*"}, {"status": "unaffected", "version": "6.12.96", "versionType": "semver", "lessThanOrEqual": "6.12.*"}, {"status": "unaffected", "version": "6.18.39", "versionType": "semver", "lessThanOrEqual": "6.18.*"}, {"status": "unaffected", "version": "7.1.4", "versionType": "semver", "lessThanOrEqual": "7.1.*"}, {"status": "unaffected", "version": "7.2", "versionType": "original_commit_for_fix", "lessThanOrEqual": "*"}], "programFiles": ["fs/nfs/dir.c"], "defaultStatus": "affected"}], "references": [{"url": "https://git.kernel.org/stable/c/4817c8974315b666e895b7d1bb83cd3664c323b1"}, {"url": "https://git.kernel.org/stable/c/cb148a2762d644bff1894728e8835a9a4b84f9ea"}, {"url": "https://git.kernel.org/stable/c/30fdf4df6c3c00efec947e4ddf97f0fdd4473628"}, {"url": "https://git.kernel.org/stable/c/22c1fd1355ad4ca27aa7f0fa02719122dd92d9de"}, {"url": "https://git.kernel.org/stable/c/6bd7d0a06b53c4e797e1a9cea0d2d41aa1b26230"}, {"url": "https://git.kernel.org/stable/c/a937e92c1d00534b5c2e3e9f4381b7e988180797"}, {"url": "https://git.kernel.org/stable/c/e36501b7d4abdcd6d69a7cb901b2f286b7a3d041"}, {"url": "https://git.kernel.org/stable/c/5140f099ecd8a2f2808b7f7b720ee1bad8468974"}], "x_generator": {"engine": "bippy-1.2.0"}, "descriptions": [{"lang": "en", "value": "In the Linux kernel, the following vulnerability has been resolved:\n\nNFSv4: include MAY_WRITE in open permission mask for O_TRUNC\n\nPOSIX requires write permission to truncate a file, so an open() that\nspecifies O_TRUNC must be authorized for write access regardless of the\nO_ACCMODE access mode.\n\nnfs_open_permission_mask() builds the access mask passed to\nnfs_may_open(), which is the local authorization gate for OPENs the\nclient serves itself from a cached write delegation via the\ncan_open_delegated() path in nfs4_try_open_cached(). The mask is\nderived from O_ACCMODE alone, so an open(O_RDONLY | O_TRUNC) against a\nfile the caller cannot write requests only MAY_READ and passes the\nlocal check. The OPEN is then satisfied locally and the truncation is\nissued to the server as a SETATTR(size=0) over the delegation stateid,\nwhich the server accepts under standard write-delegation semantics.\nPOSIX requires that this open fail with EACCES.\n\nInclude MAY_WRITE in the mask whenever O_TRUNC is set so the local\ncheck matches the access the server would have enforced."}], "cpeApplicability": [{"nodes": [{"negate": false, "cpeMatch": [{"criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*", "vulnerable": true, "versionEndExcluding": "5.10.261", "versionStartIncluding": "2.6.24"}, {"criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*", "vulnerable": true, "versionEndExcluding": "5.15.212", "versionStartIncluding": "2.6.24"}, {"criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*", "vulnerable": true, "versionEndExcluding": "6.1.178", "versionStartIncluding": "2.6.24"}, {"criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*", "vulnerable": true, "versionEndExcluding": "6.6.145", "versionStartIncluding": "2.6.24"}, {"criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*", "vulnerable": true, "versionEndExcluding": "6.12.96", "versionStartIncluding": "2.6.24"}, {"criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*", "vulnerable": true, "versionEndExcluding": "6.18.39", "versionStartIncluding": "2.6.24"}, {"criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*", "vulnerable": true, "versionEndExcluding": "7.1.4", "versionStartIncluding": "2.6.24"}, {"criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*", "vulnerable": true, "versionEndExcluding": "7.2", "versionStartIncluding": "2.6.24"}], "operator": "OR"}]}], "providerMetadata": {"orgId": "416baaa9-dc9f-4396-8d5f-8c081fb06d67", "shortName": "Linux", "dateUpdated": "2026-08-17T04:52:55.989Z"}}}, "cveMetadata": {"cveId": "CVE-2026-64298", "state": "PUBLISHED", "dateUpdated": "2026-10-19T20:38:22.558Z", "dateReserved": "2026-07-19T15:36:31.778Z", "assignerOrgId": "416baaa9-dc9f-4396-8d5f-8c081fb06d67", "datePublished": "2026-07-25T08:49:35.101Z", "assignerShortName": "Linux"}, "dataVersion": "5.2"}

{"affected": [{"affectedData": [{"defaultStatus": "unaffected", "product": "Linux", "programFiles": ["fs/nfs/dir.c"], "repo": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git", "vendor": "Linux", "versions": [{"lessThan": "4817c8974315b666e895b7d1bb83cd3664c323b1", "status": "affected", "version": "af22f94ae02ab9dd4fd7fe628c8434a59cc293be", "versionType": "git"}, {"lessThan": "cb148a2762d644bff1894728e8835a9a4b84f9ea", "status": "affected", "version": "af22f94ae02ab9dd4fd7fe628c8434a59cc293be", "versionType": "git"}, {"lessThan": "30fdf4df6c3c00efec947e4ddf97f0fdd4473628", "status": "affected", "version": "af22f94ae02ab9dd4fd7fe628c8434a59cc293be", "versionType": "git"}, {"lessThan": "22c1fd1355ad4ca27aa7f0fa02719122dd92d9de", "status": "affected", "version": "af22f94ae02ab9dd4fd7fe628c8434a59cc293be", "versionType": "git"}, {"lessThan": "6bd7d0a06b53c4e797e1a9cea0d2d41aa1b26230", "status": "affected", "version": "af22f94ae02ab9dd4fd7fe628c8434a59cc293be", "versionType": "git"}, {"lessThan": "a937e92c1d00534b5c2e3e9f4381b7e988180797", "status": "affected", "version": "af22f94ae02ab9dd4fd7fe628c8434a59cc293be", "versionType": "git"}, {"lessThan": "e36501b7d4abdcd6d69a7cb901b2f286b7a3d041", "status": "affected", "version": "af22f94ae02ab9dd4fd7fe628c8434a59cc293be", "versionType": "git"}, {"lessThan": "5140f099ecd8a2f2808b7f7b720ee1bad8468974", "status": "affected", "version": "af22f94ae02ab9dd4fd7fe628c8434a59cc293be", "versionType": "git"}]}, {"defaultStatus": "affected", "product": "Linux", "programFiles": ["fs/nfs/dir.c"], "repo": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git", "vendor": "Linux", "versions": [{"status": "affected", "version": "2.6.24"}, {"lessThan": "2.6.24", "status": "unaffected", "version": "0", "versionType": "semver"}, {"lessThanOrEqual": "5.10.*", "status": "unaffected", "version": "5.10.261", "versionType": "semver"}, {"lessThanOrEqual": "5.15.*", "status": "unaffected", "version": "5.15.212", "versionType": "semver"}, {"lessThanOrEqual": "6.1.*", "status": "unaffected", "version": "6.1.178", "versionType": "semver"}, {"lessThanOrEqual": "6.6.*", "status": "unaffected", "version": "6.6.145", "versionType": "semver"}, {"lessThanOrEqual": "6.12.*", "status": "unaffected", "version": "6.12.96", "versionType": "semver"}, {"lessThanOrEqual": "6.18.*", "status": "unaffected", "version": "6.18.39", "versionType": "semver"}, {"lessThanOrEqual": "7.1.*", "status": "unaffected", "version": "7.1.4", "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": "E2537135-6663-4C5E-A3BC-D6A2AC03BE8B", "versionEndExcluding": "5.10.261", "versionStartIncluding": "2.6.24", "vulnerable": true}, {"criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*", "matchCriteriaId": "8E99FB01-CD93-41AF-A653-3F450652B9A6", "versionEndExcluding": "5.15.212", "versionStartIncluding": "5.11", "vulnerable": true}, {"criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*", "matchCriteriaId": "092233C7-F4E0-40C8-BD4D-A28FE50DFE20", "versionEndExcluding": "6.1.178", "versionStartIncluding": "5.16", "vulnerable": true}, {"criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*", "matchCriteriaId": "7046B092-F810-4440-ACE6-60218518EECE", "versionEndExcluding": "6.6.145", "versionStartIncluding": "6.2", "vulnerable": true}, {"criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*", "matchCriteriaId": "38A8100E-2B1A-462F-AEE9-8901B870FEF2", "versionEndExcluding": "6.12.96", "versionStartIncluding": "6.7", "vulnerable": true}, {"criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*", "matchCriteriaId": "914AE4BC-3D59-4C5A-9DB5-9CE327B429F7", "versionEndExcluding": "6.18.39", "versionStartIncluding": "6.13", "vulnerable": true}, {"criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*", "matchCriteriaId": "6228DDD6-4557-4AA3-9F43-AB995D471E42", "versionEndExcluding": "7.1.4", "versionStartIncluding": "6.19", "vulnerable": true}, {"criteria": "cpe:2.3:o:linux:linux_kernel:7.2:rc1:*:*:*:*:*:*", "matchCriteriaId": "5E8B9085-7ADB-4A05-89EF-12949B6A0509", "vulnerable": true}, {"criteria": "cpe:2.3:o:linux:linux_kernel:7.2:rc2:*:*:*:*:*:*", "matchCriteriaId": "1FC0D50D-9D58-4947-A197-A5A3FF07E7E3", "vulnerable": true}], "negate": false, "operator": "OR"}]}], "cveTags": [], "descriptions": [{"lang": "en", "value": "In the Linux kernel, the following vulnerability has been resolved:\n\nNFSv4: include MAY_WRITE in open permission mask for O_TRUNC\n\nPOSIX requires write permission to truncate a file, so an open() that\nspecifies O_TRUNC must be authorized for write access regardless of the\nO_ACCMODE access mode.\n\nnfs_open_permission_mask() builds the access mask passed to\nnfs_may_open(), which is the local authorization gate for OPENs the\nclient serves itself from a cached write delegation via the\ncan_open_delegated() path in nfs4_try_open_cached(). The mask is\nderived from O_ACCMODE alone, so an open(O_RDONLY | O_TRUNC) against a\nfile the caller cannot write requests only MAY_READ and passes the\nlocal check. The OPEN is then satisfied locally and the truncation is\nissued to the server as a SETATTR(size=0) over the delegation stateid,\nwhich the server accepts under standard write-delegation semantics.\nPOSIX requires that this open fail with EACCES.\n\nInclude MAY_WRITE in the mask whenever O_TRUNC is set so the local\ncheck matches the access the server would have enforced."}], "id": "CVE-2026-64298", "lastModified": "2026-10-19T21:17:30.313", "metrics": {"cvssMetricV31": [{"cvssData": {"attackComplexity": "LOW", "attackVector": "LOCAL", "availabilityImpact": "HIGH", "baseScore": 7.1, "baseSeverity": "HIGH", "confidentialityImpact": "NONE", "integrityImpact": "HIGH", "privilegesRequired": "LOW", "scope": "UNCHANGED", "userInteraction": "NONE", "vectorString": "CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:N/I:H/A:H", "version": "3.1"}, "exploitabilityScore": 1.8, "impactScore": 5.2, "source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67", "type": "Secondary"}], "ssvcV203": [{"source": "134c704f-9b21-4f2e-91b3-4a467353bcc0", "ssvcData": {"id": "CVE-2026-64298", "options": [{"exploitation": "none"}, {"automatable": "no"}, {"technicalImpact": "partial"}], "role": "CISA Coordinator", "timestamp": "2026-10-16T15:38:37.476153Z", "version": "2.0.3"}}]}, "published": "2026-07-25T10:17:10.657", "references": [{"source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67", "tags": ["Patch"], "url": "https://git.kernel.org/stable/c/22c1fd1355ad4ca27aa7f0fa02719122dd92d9de"}, {"source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67", "tags": ["Patch"], "url": "https://git.kernel.org/stable/c/30fdf4df6c3c00efec947e4ddf97f0fdd4473628"}, {"source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67", "tags": ["Patch"], "url": "https://git.kernel.org/stable/c/4817c8974315b666e895b7d1bb83cd3664c323b1"}, {"source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67", "tags": ["Patch"], "url": "https://git.kernel.org/stable/c/5140f099ecd8a2f2808b7f7b720ee1bad8468974"}, {"source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67", "tags": ["Patch"], "url": "https://git.kernel.org/stable/c/6bd7d0a06b53c4e797e1a9cea0d2d41aa1b26230"}, {"source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67", "tags": ["Patch"], "url": "https://git.kernel.org/stable/c/a937e92c1d00534b5c2e3e9f4381b7e988180797"}, {"source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67", "tags": ["Patch"], "url": "https://git.kernel.org/stable/c/cb148a2762d644bff1894728e8835a9a4b84f9ea"}, {"source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67", "tags": ["Patch"], "url": "https://git.kernel.org/stable/c/e36501b7d4abdcd6d69a7cb901b2f286b7a3d041"}], "sourceIdentifier": "416baaa9-dc9f-4396-8d5f-8c081fb06d67", "vulnStatus": "Modified", "weaknesses": [{"description": [{"lang": "en", "value": "NVD-CWE-noinfo"}], "source": "nvd@nist.gov", "type": "Primary"}, {"description": [{"lang": "en", "value": "CWE-862"}], "source": "134c704f-9b21-4f2e-91b3-4a467353bcc0", "type": "Secondary"}]}

{"bugzilla": {"description": "kernel: NFSv4: include MAY_WRITE in open permission mask for O_TRUNC", "id": "2507208", "url": "https://bugzilla.redhat.com/show_bug.cgi?id=2507208"}, "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-358", "details": ["A flaw was found in the Linux kernel's NFSv4 implementation. A local user could exploit a vulnerability where opening a file with O_TRUNC (truncate) and O_RDONLY (read-only) flags would bypass the necessary write permission checks. This oversight allows an attacker to truncate a file without having explicit write access, leading to unauthorized data modification."], "name": "CVE-2026-64298", "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": "Affected", "package_name": "kernel", "product_name": "Red Hat Enterprise Linux 7"}, {"cpe": "cpe:/o:redhat:enterprise_linux:7", "fix_state": "Affected", "package_name": "kernel-rt", "product_name": "Red Hat Enterprise Linux 7"}, {"cpe": "cpe:/o:redhat:enterprise_linux:8", "fix_state": "Affected", "package_name": "kernel", "product_name": "Red Hat Enterprise Linux 8"}, {"cpe": "cpe:/o:redhat:enterprise_linux:8", "fix_state": "Affected", "package_name": "kernel-rt", "product_name": "Red Hat Enterprise Linux 8"}, {"cpe": "cpe:/o:redhat:enterprise_linux:9", "fix_state": "Affected", "package_name": "kernel", "product_name": "Red Hat Enterprise Linux 9"}, {"cpe": "cpe:/o:redhat:enterprise_linux:9", "fix_state": "Affected", "package_name": "kernel-rt", "product_name": "Red Hat Enterprise Linux 9"}], "public_date": "2026-07-25T00:00:00Z", "references": ["https://www.cve.org/CVERecord?id=CVE-2026-64298\nhttps://nvd.nist.gov/vuln/detail/CVE-2026-64298\nhttps://lore.kernel.org/linux-cve-announce/2026072506-CVE-2026-64298-f748@gregkh/T"], "threat_severity": "Moderate"}

{"affected": [{"configurations": [{"platform": null, "status": "affected", "versions": {"scheme": "code_commit", "value": "[af22f94ae02ab9dd4fd7fe628c8434a59cc293be,4817c8974315b666e895b7d1bb83cd3664c323b1)"}}, {"platform": null, "status": "affected", "versions": {"scheme": "code_commit", "value": "[af22f94ae02ab9dd4fd7fe628c8434a59cc293be,cb148a2762d644bff1894728e8835a9a4b84f9ea)"}}, {"platform": null, "status": "affected", "versions": {"scheme": "code_commit", "value": "[af22f94ae02ab9dd4fd7fe628c8434a59cc293be,30fdf4df6c3c00efec947e4ddf97f0fdd4473628)"}}, {"platform": null, "status": "affected", "versions": {"scheme": "code_commit", "value": "[af22f94ae02ab9dd4fd7fe628c8434a59cc293be,22c1fd1355ad4ca27aa7f0fa02719122dd92d9de)"}}, {"platform": null, "status": "affected", "versions": {"scheme": "code_commit", "value": "[af22f94ae02ab9dd4fd7fe628c8434a59cc293be,6bd7d0a06b53c4e797e1a9cea0d2d41aa1b26230)"}}, {"platform": null, "status": "affected", "versions": {"scheme": "code_commit", "value": "[af22f94ae02ab9dd4fd7fe628c8434a59cc293be,a937e92c1d00534b5c2e3e9f4381b7e988180797)"}}, {"platform": null, "status": "affected", "versions": {"scheme": "code_commit", "value": "[af22f94ae02ab9dd4fd7fe628c8434a59cc293be,e36501b7d4abdcd6d69a7cb901b2f286b7a3d041)"}}, {"platform": null, "status": "affected", "versions": {"scheme": "code_commit", "value": "[af22f94ae02ab9dd4fd7fe628c8434a59cc293be,5140f099ecd8a2f2808b7f7b720ee1bad8468974)"}}], "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": "semver", "value": "2.6.24"}}, {"platform": null, "status": "unaffected", "versions": {"scheme": "semver", "value": "[0,2.6.24)"}}, {"platform": null, "status": "unaffected", "versions": {"scheme": "semver", "value": "[5.10.261,5.11.0)"}}, {"platform": null, "status": "unaffected", "versions": {"scheme": "semver", "value": "[5.15.212,5.16.0)"}}, {"platform": null, "status": "unaffected", "versions": {"scheme": "semver", "value": "[6.1.178,6.2.0)"}}, {"platform": null, "status": "unaffected", "versions": {"scheme": "semver", "value": "[6.6.145,6.7.0)"}}, {"platform": null, "status": "unaffected", "versions": {"scheme": "semver", "value": "[6.12.96,6.13.0)"}}, {"platform": null, "status": "unaffected", "versions": {"scheme": "semver", "value": "[6.18.39,6.19.0)"}}, {"platform": null, "status": "unaffected", "versions": {"scheme": "semver", "value": "[7.1.4,7.2.0)"}}, {"platform": null, "status": "unaffected", "versions": {"scheme": "generic", "value": "[7.2-rc3,*]"}}], "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": "2026-07-25T21:45:16.674771+00:00", "updated": "2026-10-20T09:30:12.549220+00:00", "vendors": ["linux", "linux$PRODUCT$linux_kernel"]}