{"api_version":"1","generated_at":"2026-07-23T13:26:46+00:00","cve":"CVE-2026-53391","urls":{"html":"https://cve.report/CVE-2026-53391","api":"https://cve.report/api/cve/CVE-2026-53391.json","docs":"https://cve.report/api","cve_org":"https://www.cve.org/CVERecord?id=CVE-2026-53391","nvd":"https://nvd.nist.gov/vuln/detail/CVE-2026-53391"},"summary":{"title":"NFSv4/pNFS: reject zero-length r_addr in nfs4_decode_mp_ds_addr","description":"In the Linux kernel, the following vulnerability has been resolved:\n\nNFSv4/pNFS: reject zero-length r_addr in nfs4_decode_mp_ds_addr\n\nnfs4_decode_mp_ds_addr() decodes the r_netid and r_addr opaques of a\nnetaddr4 from a GETDEVICEINFO multipath-DS body, then immediately\ncalls strrchr(buf, '.') to locate the port separator. Both decodes\nuse xdr_stream_decode_string_dup(), and the current code checks only\n\"nlen < 0\" / \"rlen < 0\" before dereferencing the returned string.\n\nWhen the on-wire opaque has length zero, xdr_stream_decode_opaque_inline()\nreturns 0 and xdr_stream_decode_string_dup() falls through to its\n\"*str = NULL; return ret\" tail, leaving buf NULL with a return value\nof 0. The \"< 0\" check does not catch this, and the next line is\nstrrchr(NULL, '.'), a kernel NULL pointer dereference reachable from\nany pNFS-flexfile client mounted against a malicious or compromised\nmetadata server.\n\nReject the zero-length cases explicitly so the decoder fails with\n-EBADMSG (treated as a malformed GETDEVICEINFO body) instead of\npanicking the client.","state":"PUBLISHED","assigner":"Linux","published_at":"2026-07-19 12:16:50","updated_at":"2026-07-20 15:16:41"},"problem_types":[],"metrics":[{"version":"3.1","source":"416baaa9-dc9f-4396-8d5f-8c081fb06d67","type":"Secondary","score":"7.5","severity":"HIGH","vector":"CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H","data":{"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","attackVector":"NETWORK","attackComplexity":"LOW","privilegesRequired":"NONE","userInteraction":"NONE","scope":"UNCHANGED","confidentialityImpact":"NONE","integrityImpact":"NONE","availabilityImpact":"HIGH"}},{"version":"3.1","source":"CNA","type":"DECLARED","score":"7.5","severity":"HIGH","vector":"CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H","data":{"baseScore":7.5,"baseSeverity":"HIGH","vectorString":"CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H","version":"3.1"}}],"references":[{"url":"https://git.kernel.org/stable/c/012d37a568bfbb2c9686f03ade75560bc7139956","name":"https://git.kernel.org/stable/c/012d37a568bfbb2c9686f03ade75560bc7139956","refsource":"416baaa9-dc9f-4396-8d5f-8c081fb06d67","tags":[],"title":"","mime":"","httpstatus":"","archivestatus":"0"},{"url":"https://git.kernel.org/stable/c/76b94cbd32aacf36a641956385a852635c6802b9","name":"https://git.kernel.org/stable/c/76b94cbd32aacf36a641956385a852635c6802b9","refsource":"416baaa9-dc9f-4396-8d5f-8c081fb06d67","tags":[],"title":"","mime":"","httpstatus":"","archivestatus":"0"},{"url":"https://git.kernel.org/stable/c/41fe0f7b84f0cb822ae10ab08592996a592b2a25","name":"https://git.kernel.org/stable/c/41fe0f7b84f0cb822ae10ab08592996a592b2a25","refsource":"416baaa9-dc9f-4396-8d5f-8c081fb06d67","tags":[],"title":"","mime":"","httpstatus":"","archivestatus":"0"},{"url":"https://git.kernel.org/stable/c/427ab81a811dab4bca9d19f82eec5847ae42646e","name":"https://git.kernel.org/stable/c/427ab81a811dab4bca9d19f82eec5847ae42646e","refsource":"416baaa9-dc9f-4396-8d5f-8c081fb06d67","tags":[],"title":"","mime":"","httpstatus":"","archivestatus":"0"},{"url":"https://git.kernel.org/stable/c/c8e4e0c701d0192a2efb6df059c0f9e19678c23d","name":"https://git.kernel.org/stable/c/c8e4e0c701d0192a2efb6df059c0f9e19678c23d","refsource":"416baaa9-dc9f-4396-8d5f-8c081fb06d67","tags":[],"title":"","mime":"","httpstatus":"","archivestatus":"0"},{"url":"https://git.kernel.org/stable/c/30aae62e50b4e074a90a9a5e15246548fbdc1182","name":"https://git.kernel.org/stable/c/30aae62e50b4e074a90a9a5e15246548fbdc1182","refsource":"416baaa9-dc9f-4396-8d5f-8c081fb06d67","tags":[],"title":"","mime":"","httpstatus":"","archivestatus":"0"},{"url":"https://git.kernel.org/stable/c/6c344fff2feff9d4d716d8e4ad40e9b5040ee5ea","name":"https://git.kernel.org/stable/c/6c344fff2feff9d4d716d8e4ad40e9b5040ee5ea","refsource":"416baaa9-dc9f-4396-8d5f-8c081fb06d67","tags":[],"title":"","mime":"","httpstatus":"","archivestatus":"0"},{"url":"https://www.cve.org/CVERecord?id=CVE-2026-53391","name":"CVE Program record","refsource":"CVE.ORG","tags":["canonical"]},{"url":"https://nvd.nist.gov/vuln/detail/CVE-2026-53391","name":"NVD vulnerability detail","refsource":"NVD","tags":["canonical","analysis"]}],"affected":[{"source":"CNA","vendor":"Linux","product":"Linux","version":"affected 6b7f3cf96364eaf597940cb5c68a682894829915 76b94cbd32aacf36a641956385a852635c6802b9 git","platforms":[]},{"source":"CNA","vendor":"Linux","product":"Linux","version":"affected 6b7f3cf96364eaf597940cb5c68a682894829915 c8e4e0c701d0192a2efb6df059c0f9e19678c23d git","platforms":[]},{"source":"CNA","vendor":"Linux","product":"Linux","version":"affected 6b7f3cf96364eaf597940cb5c68a682894829915 6c344fff2feff9d4d716d8e4ad40e9b5040ee5ea git","platforms":[]},{"source":"CNA","vendor":"Linux","product":"Linux","version":"affected 6b7f3cf96364eaf597940cb5c68a682894829915 427ab81a811dab4bca9d19f82eec5847ae42646e git","platforms":[]},{"source":"CNA","vendor":"Linux","product":"Linux","version":"affected 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semver","platforms":[]},{"source":"CNA","vendor":"Linux","product":"Linux","version":"unaffected 6.12.95 6.12.* semver","platforms":[]},{"source":"CNA","vendor":"Linux","product":"Linux","version":"unaffected 6.18.38 6.18.* semver","platforms":[]},{"source":"CNA","vendor":"Linux","product":"Linux","version":"unaffected 7.1.3 7.1.* semver","platforms":[]},{"source":"CNA","vendor":"Linux","product":"Linux","version":"unaffected 7.2-rc1 * original_commit_for_fix","platforms":[]}],"timeline":[],"solutions":[],"workarounds":[],"exploits":[],"credits":[],"nvd_cpes":[],"vendor_comments":[],"enrichments":{"kev":null,"epss":{"cve_year":"2026","cve_id":"53391","cve":"CVE-2026-53391","epss":"0.001730000","percentile":"0.069380000","score_date":"2026-07-20","updated_at":"2026-07-21 00:13:14"},"legacy_qids":[]},"source_records":{"cve_program":{"containers":{"cna":{"affected":[{"defaultStatus":"unaffected","product":"Linux","programFiles":["fs/nfs/pnfs_nfs.c"],"repo":"https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git","vendor":"Linux","versions":[{"lessThan":"76b94cbd32aacf36a641956385a852635c6802b9","status":"affected","version":"6b7f3cf96364eaf597940cb5c68a682894829915","versionType":"git"},{"lessThan":"c8e4e0c701d0192a2efb6df059c0f9e19678c23d","status":"affected","version":"6b7f3cf96364eaf597940cb5c68a682894829915","versionType":"git"},{"lessThan":"6c344fff2feff9d4d716d8e4ad40e9b5040ee5ea","status":"affected","version":"6b7f3cf96364eaf597940cb5c68a682894829915","versionType":"git"},{"lessThan":"427ab81a811dab4bca9d19f82eec5847ae42646e","status":"affected","version":"6b7f3cf96364eaf597940cb5c68a682894829915","versionType":"git"},{"lessThan":"012d37a568bfbb2c9686f03ade75560bc7139956","status":"affected","version":"6b7f3cf96364eaf597940cb5c68a682894829915","versionType":"git"},{"lessThan":"30aae62e50b4e074a90a9a5e15246548fbdc1182","status":"affected","version":"6b7f3cf96364eaf597940cb5c68a682894829915","versionType":"git"},{"lessThan":"41fe0f7b84f0cb822ae10ab08592996a592b2a25","status":"affected","version":"6b7f3cf96364eaf597940cb5c68a682894829915","versionType":"git"}]},{"defaultStatus":"affected","product":"Linux","programFiles":["fs/nfs/pnfs_nfs.c"],"repo":"https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git","vendor":"Linux","versions":[{"status":"affected","version":"4.0"},{"lessThan":"4.0","status":"unaffected","version":"0","versionType":"semver"},{"lessThanOrEqual":"5.15.*","status":"unaffected","version":"5.15.211","versionType":"semver"},{"lessThanOrEqual":"6.1.*","status":"unaffected","version":"6.1.177","versionType":"semver"},{"lessThanOrEqual":"6.6.*","status":"unaffected","version":"6.6.144","versionType":"semver"},{"lessThanOrEqual":"6.12.*","status":"unaffected","version":"6.12.95","versionType":"semver"},{"lessThanOrEqual":"6.18.*","status":"unaffected","version":"6.18.38","versionType":"semver"},{"lessThanOrEqual":"7.1.*","status":"unaffected","version":"7.1.3","versionType":"semver"},{"lessThanOrEqual":"*","status":"unaffected","version":"7.2-rc1","versionType":"original_commit_for_fix"}]}],"cpeApplicability":[{"nodes":[{"cpeMatch":[{"criteria":"cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*","versionEndExcluding":"5.15.211","versionStartIncluding":"4.0","vulnerable":true},{"criteria":"cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*","versionEndExcluding":"6.1.177","versionStartIncluding":"4.0","vulnerable":true},{"criteria":"cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*","versionEndExcluding":"6.6.144","versionStartIncluding":"4.0","vulnerable":true},{"criteria":"cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*","versionEndExcluding":"6.12.95","versionStartIncluding":"4.0","vulnerable":true},{"criteria":"cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*","versionEndExcluding":"6.18.38","versionStartIncluding":"4.0","vulnerable":true},{"criteria":"cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*","versionEndExcluding":"7.1.3","versionStartIncluding":"4.0","vulnerable":true},{"criteria":"cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*","versionEndExcluding":"7.2-rc1","versionStartIncluding":"4.0","vulnerable":true}],"negate":false,"operator":"OR"}]}],"descriptions":[{"lang":"en","value":"In the Linux kernel, the following vulnerability has been resolved:\n\nNFSv4/pNFS: reject zero-length r_addr in nfs4_decode_mp_ds_addr\n\nnfs4_decode_mp_ds_addr() decodes the r_netid and r_addr opaques of a\nnetaddr4 from a GETDEVICEINFO multipath-DS body, then immediately\ncalls strrchr(buf, '.') to locate the port separator. Both decodes\nuse xdr_stream_decode_string_dup(), and the current code checks only\n\"nlen < 0\" / \"rlen < 0\" before dereferencing the returned string.\n\nWhen the on-wire opaque has length zero, xdr_stream_decode_opaque_inline()\nreturns 0 and xdr_stream_decode_string_dup() falls through to its\n\"*str = NULL; return ret\" tail, leaving buf NULL with a return value\nof 0. The \"< 0\" check does not catch this, and the next line is\nstrrchr(NULL, '.'), a kernel NULL pointer dereference reachable from\nany pNFS-flexfile client mounted against a malicious or compromised\nmetadata server.\n\nReject the zero-length cases explicitly so the decoder fails with\n-EBADMSG (treated as a malformed GETDEVICEINFO body) instead of\npanicking the client."}],"metrics":[{"cvssV3_1":{"baseScore":7.5,"baseSeverity":"HIGH","vectorString":"CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H","version":"3.1"}}],"providerMetadata":{"dateUpdated":"2026-07-20T13:39:54.843Z","orgId":"416baaa9-dc9f-4396-8d5f-8c081fb06d67","shortName":"Linux"},"references":[{"url":"https://git.kernel.org/stable/c/76b94cbd32aacf36a641956385a852635c6802b9"},{"url":"https://git.kernel.org/stable/c/c8e4e0c701d0192a2efb6df059c0f9e19678c23d"},{"url":"https://git.kernel.org/stable/c/6c344fff2feff9d4d716d8e4ad40e9b5040ee5ea"},{"url":"https://git.kernel.org/stable/c/427ab81a811dab4bca9d19f82eec5847ae42646e"},{"url":"https://git.kernel.org/stable/c/012d37a568bfbb2c9686f03ade75560bc7139956"},{"url":"https://git.kernel.org/stable/c/30aae62e50b4e074a90a9a5e15246548fbdc1182"},{"url":"https://git.kernel.org/stable/c/41fe0f7b84f0cb822ae10ab08592996a592b2a25"}],"title":"NFSv4/pNFS: reject zero-length r_addr in nfs4_decode_mp_ds_addr","x_generator":{"engine":"bippy-1.2.0"}}},"cveMetadata":{"assignerOrgId":"416baaa9-dc9f-4396-8d5f-8c081fb06d67","assignerShortName":"Linux","cveId":"CVE-2026-53391","datePublished":"2026-07-19T12:01:55.521Z","dateReserved":"2026-06-09T07:44:35.402Z","dateUpdated":"2026-07-20T13:39:54.843Z","state":"PUBLISHED"},"dataType":"CVE_RECORD","dataVersion":"5.2"},"nvd":{"publishedDate":"2026-07-19 12:16:50","lastModifiedDate":"2026-07-20 15:16:41","problem_types":[],"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:N/I:N/A:H","baseScore":7.5,"baseSeverity":"HIGH","attackVector":"NETWORK","attackComplexity":"LOW","privilegesRequired":"NONE","userInteraction":"NONE","scope":"UNCHANGED","confidentialityImpact":"NONE","integrityImpact":"NONE","availabilityImpact":"HIGH"},"exploitabilityScore":3.9,"impactScore":3.6}]},"configurations":[]},"legacy_mitre":{"record":{"CveYear":"2026","CveId":"53391","Ordinal":"1","Title":"NFSv4/pNFS: reject zero-length r_addr in nfs4_decode_mp_ds_addr","CVE":"CVE-2026-53391","Year":"2026"},"notes":[{"CveYear":"2026","CveId":"53391","Ordinal":"1","NoteData":"In the Linux kernel, the following vulnerability has been resolved:\n\nNFSv4/pNFS: reject zero-length r_addr in nfs4_decode_mp_ds_addr\n\nnfs4_decode_mp_ds_addr() decodes the r_netid and r_addr opaques of a\nnetaddr4 from a GETDEVICEINFO multipath-DS body, then immediately\ncalls strrchr(buf, '.') to locate the port separator. Both decodes\nuse xdr_stream_decode_string_dup(), and the current code checks only\n\"nlen < 0\" / \"rlen < 0\" before dereferencing the returned string.\n\nWhen the on-wire opaque has length zero, xdr_stream_decode_opaque_inline()\nreturns 0 and xdr_stream_decode_string_dup() falls through to its\n\"*str = NULL; return ret\" tail, leaving buf NULL with a return value\nof 0. The \"< 0\" check does not catch this, and the next line is\nstrrchr(NULL, '.'), a kernel NULL pointer dereference reachable from\nany pNFS-flexfile client mounted against a malicious or compromised\nmetadata server.\n\nReject the zero-length cases explicitly so the decoder fails with\n-EBADMSG (treated as a malformed GETDEVICEINFO body) instead of\npanicking the client.","Type":"Description","Title":"NFSv4/pNFS: reject zero-length r_addr in nfs4_decode_mp_ds_addr"}]}}}