{"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"}}}}