{ "dataType": "CVE_RECORD", "dataVersion": "5.2", "cveMetadata": { "cveId": "CVE-2026-53391", "assignerOrgId": "416baaa9-dc9f-4396-8d5f-8c081fb06d67", "state": "PUBLISHED", "assignerShortName": "Linux", "dateReserved": "2026-06-09T07:44:35.402Z", "datePublished": "2026-07-19T12:01:55.521Z", "dateUpdated": "2026-08-17T04:50:42.650Z" }, "containers": { "cna": { "providerMetadata": { "orgId": "416baaa9-dc9f-4396-8d5f-8c081fb06d67", "shortName": "Linux", "dateUpdated": "2026-08-17T04:50:42.650Z" }, "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": { "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 crash is triggered by processing a malicious GETDEVICEINFO RPC response from an NFS metadata server over the network, on the standard NFSv4 client path used by pNFS file and flexfile layouts.\nAC:L - Once a victim is a pNFS client, the attacker reliably triggers the bug by sending a GETDEVICEINFO body with a zero-length r_netid or r_addr opaque; no race or special memory layout is required.\nPR:N - The attacker acts as (or compromises) the remote NFS metadata server and needs no local privileges on the victim client; exploitation is delivered entirely through NFS protocol responses to an already-established mount.\nUI:N - In the highest-impact scenario—a compromised enterprise/HPC metadata server or autofs-managed pNFS mount—no further victim action is needed beyond normal file I/O that provokes GETDEVICEINFO.\nS:U - The vulnerability causes a kernel panic on the NFS client itself and does not cross a security boundary such as a VM escape or sandbox breakout.\nC:N - This is a NULL pointer dereference in strrchr() with no out-of-bounds read or use-after-free; it does not disclose kernel memory or attacker-controlled data.\nI:N - There is no memory corruption, arbitrary write, or control-flow hijack primitive—only an immediate NULL dereference that terminates kernel execution.\nA:H - The NULL pointer dereference in kernel context causes an oops or panic, fully denying availability of the affected client (and any co-hosted workloads until reboot)." } ] } ], "affected": [ { "product": "Linux", "vendor": "Linux", "defaultStatus": "unaffected", "repo": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git", "programFiles": [ "fs/nfs/pnfs_nfs.c" ], "versions": [ { "version": "6b7f3cf96364eaf597940cb5c68a682894829915", "lessThan": "76b94cbd32aacf36a641956385a852635c6802b9", "status": "affected", "versionType": "git" }, { "version": "6b7f3cf96364eaf597940cb5c68a682894829915", "lessThan": "c8e4e0c701d0192a2efb6df059c0f9e19678c23d", "status": "affected", "versionType": "git" }, { "version": "6b7f3cf96364eaf597940cb5c68a682894829915", "lessThan": "6c344fff2feff9d4d716d8e4ad40e9b5040ee5ea", "status": "affected", "versionType": "git" }, { "version": "6b7f3cf96364eaf597940cb5c68a682894829915", "lessThan": "427ab81a811dab4bca9d19f82eec5847ae42646e", "status": "affected", "versionType": "git" }, { "version": "6b7f3cf96364eaf597940cb5c68a682894829915", "lessThan": "012d37a568bfbb2c9686f03ade75560bc7139956", "status": "affected", "versionType": "git" }, { "version": "6b7f3cf96364eaf597940cb5c68a682894829915", "lessThan": "30aae62e50b4e074a90a9a5e15246548fbdc1182", "status": "affected", "versionType": "git" }, { "version": "6b7f3cf96364eaf597940cb5c68a682894829915", "lessThan": "41fe0f7b84f0cb822ae10ab08592996a592b2a25", "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/pnfs_nfs.c" ], "versions": [ { "version": "4.0", "status": "affected" }, { "version": "0", "lessThan": "4.0", "status": "unaffected", "versionType": "semver" }, { "version": "5.15.211", "lessThanOrEqual": "5.15.*", "status": "unaffected", "versionType": "semver" }, { "version": "6.1.177", "lessThanOrEqual": "6.1.*", "status": "unaffected", "versionType": "semver" }, { "version": "6.6.144", "lessThanOrEqual": "6.6.*", "status": "unaffected", "versionType": "semver" }, { "version": "6.12.95", "lessThanOrEqual": "6.12.*", "status": "unaffected", "versionType": "semver" }, { "version": "6.18.38", "lessThanOrEqual": "6.18.*", "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": "4.0", "versionEndExcluding": "5.15.211" }, { "vulnerable": true, "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*", "versionStartIncluding": "4.0", "versionEndExcluding": "6.1.177" }, { "vulnerable": true, "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*", "versionStartIncluding": "4.0", "versionEndExcluding": "6.6.144" }, { "vulnerable": true, "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*", "versionStartIncluding": "4.0", "versionEndExcluding": "6.12.95" }, { "vulnerable": true, "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*", "versionStartIncluding": "4.0", "versionEndExcluding": "6.18.38" }, { "vulnerable": true, "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*", "versionStartIncluding": "4.0", "versionEndExcluding": "7.1.3" }, { "vulnerable": true, "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*", "versionStartIncluding": "4.0", "versionEndExcluding": "7.2" } ] } ] } ], "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" } } } }