{ "dataType": "CVE_RECORD", "dataVersion": "5.2", "cveMetadata": { "cveId": "CVE-2026-74730", "assignerOrgId": "416baaa9-dc9f-4396-8d5f-8c081fb06d67", "state": "PUBLISHED", "assignerShortName": "Linux", "dateReserved": "2026-08-15T05:44:03.930Z", "datePublished": "2026-08-22T15:33:19.659Z", "dateUpdated": "2026-10-16T19:16:12.405Z" }, "containers": { "cna": { "providerMetadata": { "orgId": "416baaa9-dc9f-4396-8d5f-8c081fb06d67", "shortName": "Linux", "dateUpdated": "2026-08-25T05:42:09.527Z" }, "descriptions": [ { "lang": "en", "value": "In the Linux kernel, the following vulnerability has been resolved:\n\nNFS: Pin the 'struct nfs_server' during a FREE_STATEID call\n\nDan Aloni reports that he was able to hit a use-after-free bug if a\nFREE_STATEID operation gets delayed for whatever reason. Fix this by\nbumping the refcount of the 'struct nfs_server' object for the duration\nof the FREE_STATEID so it doesn't get cleaned up from underneath us\nwhile operations are still in flight." } ], "metrics": [ { "cvssV3_1": { "version": "3.1", "vectorString": "CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H", "baseScore": 9.8, "baseSeverity": "CRITICAL" }, "scenarios": [ { "lang": "en", "value": "AV:N - The bug is in the NFSv4 client FREE_STATEID path: nfs41_free_stateid_prepare/done/release use a freed struct nfs_server while handling async RPC completions driven by NFSv4 replies from the mounted server and by server-initiated CB_RECALL/CB_RECALLANY callbacks on the NFS backchannel.\nAC:L - The attacker controls both sides of the race: they provoke FREE_STATEID via revocation responses or callbacks, keep it in flight with NFS4ERR_DELAY, and time nfs_server teardown via user-mount umount, automount idle expiry, or the concurrent stateid cleanup that runs during umount itself.\nPR:N - A malicious or compromised NFSv4 server needs no account or elevated capability on the victim client once an NFSv4.1+ mount exists; FREE_STATEID is issued automatically during server-driven stateid revocation handling without any client-side privileges at exploit time.\nUI:N - After an NFS mount exists (boot-time, autofs, or Kubernetes volumes are common), no further victim action is needed: the attacker drives recall/revocation on the wire and mount teardown follows from automated autofs expiry or attacker-controlled umount on a user-mounted export.\nS:U - The use-after-free corrupts kernel heap within the NFS client on the same host; it is a standard kernel memory-safety bug, not a VM escape, container breakout, or IOMMU/DMA boundary crossing.\nC:H - Freed struct nfs_server objects are kmalloc'd and callbacks dereference nfs_client, rpc_clnt, and super_block fields after nfs_free_server/call_rcu, giving a classic UAF read primitive over attacker-influenced heap contents including function pointers.\nI:H - UAF on struct nfs_server exposes destroy hooks, RPC client handles, and client/session state pointers that an attacker can reschedule via heap grooming, yielding write and control-flow primitives typical of NFS client heap corruption bugs.\nA:H - Use of a freed nfs_server in RPC prepare/done/release paths causes kernel oops or panic; Dan Aloni demonstrated reliable reproduction, and UAFs in this path crash hosts even when not fully weaponized." } ] } ], "affected": [ { "product": "Linux", "vendor": "Linux", "defaultStatus": "unaffected", "repo": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git", "programFiles": [ "fs/nfs/nfs4proc.c" ], "versions": [ { "version": "7c1d5fae4a87d3cf3e9ffd68bcdbaf6529013009", "lessThan": "ed2f92ce2fc48463c41e0e540b9a3454889e8af8", "status": "affected", "versionType": "git" }, { "version": "7c1d5fae4a87d3cf3e9ffd68bcdbaf6529013009", "lessThan": "d858ab09e787106432d4d9830bad9dfedf02f890", "status": "affected", "versionType": "git" }, { "version": "7c1d5fae4a87d3cf3e9ffd68bcdbaf6529013009", "lessThan": "af62f1af182d33a0de38308c012841885d8ab92e", "status": "affected", "versionType": "git" }, { "version": "7c1d5fae4a87d3cf3e9ffd68bcdbaf6529013009", "lessThan": "caee6a68ffaa5016dfc01cd0b3dc1896a32e3abd", "status": "affected", "versionType": "git" }, { "version": "7c1d5fae4a87d3cf3e9ffd68bcdbaf6529013009", "lessThan": "ed1161ab6239761958b38d5667225634fc2be894", "status": "affected", "versionType": "git" }, { "version": "7c1d5fae4a87d3cf3e9ffd68bcdbaf6529013009", "lessThan": "d71dfffa512e71b166a889484e4c3b148a9a3af2", "status": "affected", "versionType": "git" }, { "version": "7c1d5fae4a87d3cf3e9ffd68bcdbaf6529013009", "lessThan": "80ed3d762628b36c9e4b22fac7c65b72ef3b13dd", "status": "affected", "versionType": "git" }, { "version": "7c1d5fae4a87d3cf3e9ffd68bcdbaf6529013009", "lessThan": "cf616096a0f3a2b60f7d68b6b39674a6867ded9c", "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/nfs4proc.c" ], "versions": [ { "version": "3.10", "status": "affected" }, { "version": "0", "lessThan": "3.10", "status": "unaffected", "versionType": "semver" }, { "version": "5.10.265", "lessThanOrEqual": "5.10.*", "status": "unaffected", "versionType": "semver" }, { "version": "5.15.216", "lessThanOrEqual": "5.15.*", "status": "unaffected", "versionType": "semver" }, { "version": "6.1.183", "lessThanOrEqual": "6.1.*", "status": "unaffected", "versionType": "semver" }, { "version": "6.6.152", "lessThanOrEqual": "6.6.*", "status": "unaffected", "versionType": "semver" }, { "version": "6.12.104", "lessThanOrEqual": "6.12.*", "status": "unaffected", "versionType": "semver" }, { "version": "6.18.45", "lessThanOrEqual": "6.18.*", "status": "unaffected", "versionType": "semver" }, { "version": "7.1.9", "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": "3.10", "versionEndExcluding": "5.10.265" }, { "vulnerable": true, "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*", "versionStartIncluding": "3.10", "versionEndExcluding": "5.15.216" }, { "vulnerable": true, "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*", "versionStartIncluding": "3.10", "versionEndExcluding": "6.1.183" }, { "vulnerable": true, "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*", "versionStartIncluding": "3.10", "versionEndExcluding": "6.6.152" }, { "vulnerable": true, "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*", "versionStartIncluding": "3.10", "versionEndExcluding": "6.12.104" }, { "vulnerable": true, "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*", "versionStartIncluding": "3.10", "versionEndExcluding": "6.18.45" }, { "vulnerable": true, "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*", "versionStartIncluding": "3.10", "versionEndExcluding": "7.1.9" }, { "vulnerable": true, "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*", "versionStartIncluding": "3.10", "versionEndExcluding": "7.2" } ] } ] } ], "references": [ { "url": "https://git.kernel.org/stable/c/ed2f92ce2fc48463c41e0e540b9a3454889e8af8" }, { "url": "https://git.kernel.org/stable/c/d858ab09e787106432d4d9830bad9dfedf02f890" }, { "url": "https://git.kernel.org/stable/c/af62f1af182d33a0de38308c012841885d8ab92e" }, { "url": "https://git.kernel.org/stable/c/caee6a68ffaa5016dfc01cd0b3dc1896a32e3abd" }, { "url": "https://git.kernel.org/stable/c/ed1161ab6239761958b38d5667225634fc2be894" }, { "url": "https://git.kernel.org/stable/c/d71dfffa512e71b166a889484e4c3b148a9a3af2" }, { "url": "https://git.kernel.org/stable/c/80ed3d762628b36c9e4b22fac7c65b72ef3b13dd" }, { "url": "https://git.kernel.org/stable/c/cf616096a0f3a2b60f7d68b6b39674a6867ded9c" } ], "title": "NFS: Pin the 'struct nfs_server' during a FREE_STATEID call", "x_generator": { "engine": "bippy-1.2.0" } }, "adp": [ { "metrics": [ { "other": { "type": "ssvc", "content": { "id": "CVE-2026-74730", "role": "CISA Coordinator", "options": [ { "Exploitation": "none" }, { "Automatable": "yes" }, { "Technical Impact": "total" } ], "version": "2.0.3", "timestamp": "2026-10-16T19:15:50.650757Z" } } } ], "title": "CISA ADP Vulnrichment", "providerMetadata": { "orgId": "134c704f-9b21-4f2e-91b3-4a467353bcc0", "shortName": "CISA-ADP", "dateUpdated": "2026-10-16T19:16:12.405Z" } } ] } }