{ "dataType": "CVE_RECORD", "dataVersion": "5.2", "cveMetadata": { "cveId": "CVE-2026-53399", "assignerOrgId": "416baaa9-dc9f-4396-8d5f-8c081fb06d67", "state": "PUBLISHED", "assignerShortName": "Linux", "dateReserved": "2026-06-09T07:44:35.402Z", "datePublished": "2026-07-19T12:02:00.055Z", "dateUpdated": "2026-08-17T04:50:51.453Z" }, "containers": { "cna": { "providerMetadata": { "orgId": "416baaa9-dc9f-4396-8d5f-8c081fb06d67", "shortName": "Linux", "dateUpdated": "2026-08-17T04:50:51.453Z" }, "descriptions": [ { "lang": "en", "value": "In the Linux kernel, the following vulnerability has been resolved:\n\nnfsd: release layout stid on setlease failure\n\nnfs4_alloc_stid() publishes the new stid into cl->cl_stateids via\nidr_alloc_cyclic() under cl_lock before returning to\nnfsd4_alloc_layout_stateid(). When nfsd4_layout_setlease() then\nfails, the error path frees the layout stateid directly with\nkmem_cache_free() without ever calling idr_remove(), leaving the\nIDR slot pointing at freed slab memory. Any subsequent IDR walker\n(states_show, client teardown) dereferences the dangling pointer.\n\nThe correct teardown for an IDR-published stid is nfs4_put_stid(),\nwhich removes the IDR slot under cl_lock, dispatches sc_free\n(nfsd4_free_layout_stateid) to release ls->ls_file via\nnfsd4_close_layout(), and drops the nfs4_file reference in its\ntail.\n\nA second issue blocks that switch: nfsd4_free_layout_stateid()\nunconditionally inspects ls->ls_fence_work via\ndelayed_work_pending() under ls_lock, but\nINIT_DELAYED_WORK(&ls->ls_fence_work, ...) currently runs only\nafter the setlease call. On the setlease-failure path the\ndestructor would touch an uninitialized delayed_work.\n\n nfsd4_alloc_layout_stateid()\n nfs4_alloc_stid() /* idr_alloc_cyclic under cl_lock */\n nfsd4_layout_setlease() /* fails */\n nfs4_put_stid()\n nfsd4_free_layout_stateid()\n delayed_work_pending(&ls->ls_fence_work) /* needs INIT */\n nfsd4_close_layout() /* nfsd_file_put(ls->ls_file) */\n put_nfs4_file()\n\nFix by hoisting the ls_fenced / ls_fence_delay / INIT_DELAYED_WORK\ninitialization above the nfsd4_layout_setlease() call, and replace\nthe manual nfsd_file_put + put_nfs4_file + kmem_cache_free cleanup\nwith a single nfs4_put_stid(stp)." } ], "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 reached through nfsd's NFSv4 OP_LAYOUTGET handler, which processes attacker-controlled RPC compounds over the network on TCP port 2049.\nAC:L - An authenticated NFS client can reliably trigger the fault by issuing LAYOUTGET on block/SCSI pNFS exports so that nfsd4_layout_setlease() fails (e.g., -ENOMEM or -EINVAL), and can retry, spray the slab, and race concurrent compounds to exploit the dangling IDR entry.\nPR:N - Exploitation requires only the ability to act as a remote NFSv4 client against an export with pNFS enabled, not local shell access or elevated privileges on the Linux host.\nUI:N - No end-user or administrator action on the server is required; the vulnerability is triggered entirely through malicious NFS protocol traffic from a network client.\nS:U - Impact is confined to kernel memory corruption and nfsd state within the same kernel security boundary, not a cross-boundary escape such as VM or container breakout.\nC:H - The IDR retains a pointer to freed layout stateid slab memory, creating a use-after-free that can be leveraged for arbitrary kernel memory reads after heap reuse.\nI:H - UAF on the layout stateid object enables controlled slab reuse and corruption of adjacent kernel structures, supporting arbitrary write or control-flow hijack primitives.\nA:H - Dereferencing the dangling IDR pointer during state iteration or stateid lookup can cause kernel oops/panic, and UAF exploitation can crash or hang the server." } ] } ], "affected": [ { "product": "Linux", "vendor": "Linux", "defaultStatus": "unaffected", "repo": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git", "programFiles": [ "fs/nfsd/nfs4layouts.c" ], "versions": [ { "version": "c5c707f96fc9a6e5a57ca5baac892673270abe3d", "lessThan": "d788ef40a7517d22c97ab01700e4ae4c611b6f2f", "status": "affected", "versionType": "git" }, { "version": "c5c707f96fc9a6e5a57ca5baac892673270abe3d", "lessThan": "2e0a5d6d62600b8c614d1b55e50ef94035d6adf9", "status": "affected", "versionType": "git" }, { "version": "c5c707f96fc9a6e5a57ca5baac892673270abe3d", "lessThan": "7bbb7ce74051c8be4b69ff44ce3db370600dae61", "status": "affected", "versionType": "git" }, { "version": "c5c707f96fc9a6e5a57ca5baac892673270abe3d", "lessThan": "48a586e382e4db1dbf958d44b63e081df5f8ed04", "status": "affected", "versionType": "git" }, { "version": "c5c707f96fc9a6e5a57ca5baac892673270abe3d", "lessThan": "d369e5edfaaf83a448016e2f1da392b2174be801", "status": "affected", "versionType": "git" }, { "version": "c5c707f96fc9a6e5a57ca5baac892673270abe3d", "lessThan": "8dee7c278f1c2b5bb80e17a6281c3812fc8b0cdd", "status": "affected", "versionType": "git" }, { "version": "c5c707f96fc9a6e5a57ca5baac892673270abe3d", "lessThan": "83c2b7797742339bb768f83935f7ca33950db138", "status": "affected", "versionType": "git" }, { "version": "c5c707f96fc9a6e5a57ca5baac892673270abe3d", "lessThan": "30d55c8aabb261bc3f427d6b9aae7ef6206063f9", "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/nfs4layouts.c" ], "versions": [ { "version": "4.0", "status": "affected" }, { "version": "0", "lessThan": "4.0", "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": "7.1.3", "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": "5.10.261" }, { "vulnerable": true, "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*", "versionStartIncluding": "4.0", "versionEndExcluding": "5.15.212" }, { "vulnerable": true, "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*", "versionStartIncluding": "4.0", "versionEndExcluding": "6.1.178" }, { "vulnerable": true, "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*", "versionStartIncluding": "4.0", "versionEndExcluding": "6.6.145" }, { "vulnerable": true, "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*", "versionStartIncluding": "4.0", "versionEndExcluding": "6.12.96" }, { "vulnerable": true, "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*", "versionStartIncluding": "4.0", "versionEndExcluding": "6.18.39" }, { "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/d788ef40a7517d22c97ab01700e4ae4c611b6f2f" }, { "url": "https://git.kernel.org/stable/c/2e0a5d6d62600b8c614d1b55e50ef94035d6adf9" }, { "url": "https://git.kernel.org/stable/c/7bbb7ce74051c8be4b69ff44ce3db370600dae61" }, { "url": "https://git.kernel.org/stable/c/48a586e382e4db1dbf958d44b63e081df5f8ed04" }, { "url": "https://git.kernel.org/stable/c/d369e5edfaaf83a448016e2f1da392b2174be801" }, { "url": "https://git.kernel.org/stable/c/8dee7c278f1c2b5bb80e17a6281c3812fc8b0cdd" }, { "url": "https://git.kernel.org/stable/c/83c2b7797742339bb768f83935f7ca33950db138" }, { "url": "https://git.kernel.org/stable/c/30d55c8aabb261bc3f427d6b9aae7ef6206063f9" } ], "title": "nfsd: release layout stid on setlease failure", "x_generator": { "engine": "bippy-1.2.0" } } } }