{"id":"CVE-2026-53398","state":"PUBLISHED","title":"NFSD: Fix SECINFO_NO_NAME decode error cleanup","description":"In the Linux kernel, the following vulnerability has been resolved:\n\nNFSD: Fix SECINFO_NO_NAME decode error cleanup\n\nnfsd4_decode_secinfo_no_name() currently initializes sin_exp after\ndecoding sin_style. If the XDR stream is truncated, the decoder returns\nnfserr_bad_xdr before sin_exp is initialized.\n\nSince commit 3fdc54646234 (\"NFSD: Reduce amount of struct\nnfsd4_compoundargs that needs clearing\"), the inline iops array is not\ncleared between RPC calls. A failed SECINFO_NO_NAME decode can therefore\nleave sin_exp holding stale union contents from a previous operation.\n\nThe error response path still invokes nfsd4_secinfo_no_name_release(),\nwhich calls exp_put() on a non-NULL sin_exp.\n\nInitialize sin_exp before the first failable decode step, matching\nnfsd4_decode_secinfo().","publishedAt":"2026-07-19T12:01:59.507Z","updatedAt":"2026-10-19T20:07:46.561Z","severity":{"score":9.8,"label":"Critical","version":"3.1","vector":"CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H","source":"Linux"},"assigner":"Linux","products":["Linux Linux"],"affected":[{"vendor":"Linux","product":"Linux","defaultStatus":"unaffected","versions":[{"version":"5e76b25d7cc82c148d391c0c43b884e6427cb302","status":"affected","lessThan":"8836405abdc53ca3dd5fc68b2cf6f8f012fad011","versionType":"git"},{"version":"07b68ff5c71cf4ed5443016d8eb116863c0a4d88","status":"affected","lessThan":"49de5d31dd8fdebf78bdeaf196b0ca5cd5c75439","versionType":"git"},{"version":"3fdc546462348b8a497c72bc894e0cde9f10fc40","status":"affected","lessThan":"5ec37edcb534f3fc92304be236d37f08e6545585","versionType":"git"},{"version":"3fdc546462348b8a497c72bc894e0cde9f10fc40","status":"affected","lessThan":"1e04be34cafae119e82bcaccd6d28a20f72a3647","versionType":"git"},{"version":"3fdc546462348b8a497c72bc894e0cde9f10fc40","status":"affected","lessThan":"161d1aaeb04d620d3692639700512bb5038c1e10","versionType":"git"},{"version":"3fdc546462348b8a497c72bc894e0cde9f10fc40","status":"affected","lessThan":"c8a24effd96d4779e2ad779654682304491c55a5","versionType":"git"},{"version":"3fdc546462348b8a497c72bc894e0cde9f10fc40","status":"affected","lessThan":"46eb17d45be69d28c7a23ea03283b207426a8232","versionType":"git"},{"version":"3fdc546462348b8a497c72bc894e0cde9f10fc40","status":"affected","lessThan":"9e18e83b8846a5c3fe13fc8a464b4865d33996c6","versionType":"git"},{"version":"5.10.220","status":"affected","lessThan":"5.10.260","versionType":"semver"},{"version":"5.15.154","status":"affected","lessThan":"5.15.211","versionType":"semver"}],"repo":"https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git","programFiles":["fs/nfsd/nfs4xdr.c"]},{"vendor":"Linux","product":"Linux","defaultStatus":"affected","versions":[{"version":"6.1","status":"affected"},{"version":"0","status":"unaffected","lessThan":"6.1","versionType":"semver"},{"version":"5.10.260","status":"unaffected","lessThanOrEqual":"5.10.*","versionType":"semver"},{"version":"5.15.211","status":"unaffected","lessThanOrEqual":"5.15.*","versionType":"semver"},{"version":"6.1.177","status":"unaffected","lessThanOrEqual":"6.1.*","versionType":"semver"},{"version":"6.6.144","status":"unaffected","lessThanOrEqual":"6.6.*","versionType":"semver"},{"version":"6.12.95","status":"unaffected","lessThanOrEqual":"6.12.*","versionType":"semver"},{"version":"6.18.38","status":"unaffected","lessThanOrEqual":"6.18.*","versionType":"semver"},{"version":"7.1.3","status":"unaffected","lessThanOrEqual":"7.1.*","versionType":"semver"},{"version":"7.2","status":"unaffected","lessThanOrEqual":"*","versionType":"original_commit_for_fix"}],"repo":"https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git","programFiles":["fs/nfsd/nfs4xdr.c"]}],"references":["https://git.kernel.org/stable/c/8836405abdc53ca3dd5fc68b2cf6f8f012fad011","https://git.kernel.org/stable/c/49de5d31dd8fdebf78bdeaf196b0ca5cd5c75439","https://git.kernel.org/stable/c/5ec37edcb534f3fc92304be236d37f08e6545585","https://git.kernel.org/stable/c/1e04be34cafae119e82bcaccd6d28a20f72a3647","https://git.kernel.org/stable/c/161d1aaeb04d620d3692639700512bb5038c1e10","https://git.kernel.org/stable/c/c8a24effd96d4779e2ad779654682304491c55a5","https://git.kernel.org/stable/c/46eb17d45be69d28c7a23ea03283b207426a8232","https://git.kernel.org/stable/c/9e18e83b8846a5c3fe13fc8a464b4865d33996c6"],"weaknesses":["CWE-665"],"ingestedAt":"2026-10-29T20:12:16.098Z","source":{"repository":"CVEProject/cvelistV5","path":"cves/2026/53xxx/CVE-2026-53398.json","commit":"556c9d3a8cd17e218bb8e452ba7cd619a384ff47"},"raw":{"dataType":"CVE_RECORD","dataVersion":"5.2","cveMetadata":{"cveId":"CVE-2026-53398","state":"PUBLISHED","datePublished":"2026-07-19T12:01:59.507Z","dateUpdated":"2026-10-19T20:07:46.561Z","assignerShortName":"Linux","assignerOrgId":"416baaa9-dc9f-4396-8d5f-8c081fb06d67","dateReserved":"2026-06-09T07:44:35.402Z"},"containers":{"cna":{"title":"NFSD: Fix SECINFO_NO_NAME decode error cleanup","descriptions":[{"lang":"en","value":"In the Linux kernel, the following vulnerability has been resolved:\n\nNFSD: Fix SECINFO_NO_NAME decode error cleanup\n\nnfsd4_decode_secinfo_no_name() currently initializes sin_exp after\ndecoding sin_style. If the XDR stream is truncated, the decoder returns\nnfserr_bad_xdr before sin_exp is initialized.\n\nSince commit 3fdc54646234 (\"NFSD: Reduce amount of struct\nnfsd4_compoundargs that needs clearing\"), the inline iops array is not\ncleared between RPC calls. A failed SECINFO_NO_NAME decode can therefore\nleave sin_exp holding stale union contents from a previous operation.\n\nThe error response path still invokes nfsd4_secinfo_no_name_release(),\nwhich calls exp_put() on a non-NULL sin_exp.\n\nInitialize sin_exp before the first failable decode step, matching\nnfsd4_decode_secinfo()."}],"affected":[{"vendor":"Linux","product":"Linux","defaultStatus":"unaffected","versions":[{"version":"5e76b25d7cc82c148d391c0c43b884e6427cb302","status":"affected","lessThan":"8836405abdc53ca3dd5fc68b2cf6f8f012fad011","versionType":"git"},{"version":"07b68ff5c71cf4ed5443016d8eb116863c0a4d88","status":"affected","lessThan":"49de5d31dd8fdebf78bdeaf196b0ca5cd5c75439","versionType":"git"},{"version":"3fdc546462348b8a497c72bc894e0cde9f10fc40","status":"affected","lessThan":"5ec37edcb534f3fc92304be236d37f08e6545585","versionType":"git"},{"version":"3fdc546462348b8a497c72bc894e0cde9f10fc40","status":"affected","lessThan":"1e04be34cafae119e82bcaccd6d28a20f72a3647","versionType":"git"},{"version":"3fdc546462348b8a497c72bc894e0cde9f10fc40","status":"affected","lessThan":"161d1aaeb04d620d3692639700512bb5038c1e10","versionType":"git"},{"version":"3fdc546462348b8a497c72bc894e0cde9f10fc40","status":"affected","lessThan":"c8a24effd96d4779e2ad779654682304491c55a5","versionType":"git"},{"version":"3fdc546462348b8a497c72bc894e0cde9f10fc40","status":"affected","lessThan":"46eb17d45be69d28c7a23ea03283b207426a8232","versionType":"git"},{"version":"3fdc546462348b8a497c72bc894e0cde9f10fc40","status":"affected","lessThan":"9e18e83b8846a5c3fe13fc8a464b4865d33996c6","versionType":"git"},{"version":"5.10.220","status":"affected","lessThan":"5.10.260","versionType":"semver"},{"version":"5.15.154","status":"affected","lessThan":"5.15.211","versionType":"semver"}],"repo":"https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git","programFiles":["fs/nfsd/nfs4xdr.c"]},{"vendor":"Linux","product":"Linux","defaultStatus":"affected","versions":[{"version":"6.1","status":"affected"},{"version":"0","status":"unaffected","lessThan":"6.1","versionType":"semver"},{"version":"5.10.260","status":"unaffected","lessThanOrEqual":"5.10.*","versionType":"semver"},{"version":"5.15.211","status":"unaffected","lessThanOrEqual":"5.15.*","versionType":"semver"},{"version":"6.1.177","status":"unaffected","lessThanOrEqual":"6.1.*","versionType":"semver"},{"version":"6.6.144","status":"unaffected","lessThanOrEqual":"6.6.*","versionType":"semver"},{"version":"6.12.95","status":"unaffected","lessThanOrEqual":"6.12.*","versionType":"semver"},{"version":"6.18.38","status":"unaffected","lessThanOrEqual":"6.18.*","versionType":"semver"},{"version":"7.1.3","status":"unaffected","lessThanOrEqual":"7.1.*","versionType":"semver"},{"version":"7.2","status":"unaffected","lessThanOrEqual":"*","versionType":"original_commit_for_fix"}],"repo":"https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git","programFiles":["fs/nfsd/nfs4xdr.c"]}],"references":[{"url":"https://git.kernel.org/stable/c/8836405abdc53ca3dd5fc68b2cf6f8f012fad011"},{"url":"https://git.kernel.org/stable/c/49de5d31dd8fdebf78bdeaf196b0ca5cd5c75439"},{"url":"https://git.kernel.org/stable/c/5ec37edcb534f3fc92304be236d37f08e6545585"},{"url":"https://git.kernel.org/stable/c/1e04be34cafae119e82bcaccd6d28a20f72a3647"},{"url":"https://git.kernel.org/stable/c/161d1aaeb04d620d3692639700512bb5038c1e10"},{"url":"https://git.kernel.org/stable/c/c8a24effd96d4779e2ad779654682304491c55a5"},{"url":"https://git.kernel.org/stable/c/46eb17d45be69d28c7a23ea03283b207426a8232"},{"url":"https://git.kernel.org/stable/c/9e18e83b8846a5c3fe13fc8a464b4865d33996c6"}],"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 nfsd4_decode_secinfo_no_name() on the NFSv4 COMPOUND RPC decode path; nfsd is an in-kernel network file server reached remotely over TCP/UDP port 2049 by any client that can connect.\nAC:L - An attacker on the same TCP connection can first send a valid SECINFO_NO_NAME compound to leave a dangling sin_exp in the reused iops[] slot, then send a truncated SECINFO_NO_NAME to trigger nfserr_bad_xdr and nfsd4_secinfo_no_name_release() without re-initializing sin_exp.\nPR:N - Exploitation requires only network reachability to nfsd and standard NFSv4.1 session setup (EXCHANGE_ID/CREATE_SESSION/SEQUENCE); default exports accept RPC_AUTH_NULL with no local privileges, matching an unauthenticated remote attacker on a misconfigured or internet-exposed NFS server.\nUI:N - No victim user action is required; the attacker triggers the bug entirely by sending crafted NFSv4 COMPOUND RPC requests to the server.\nS:U - Impact is confined to kernel nfsd/export-cache memory mismanagement on the NFS server; it does not cross a VM, container, or IOMMU security boundary.\nC:H - The stale sin_exp causes exp_put()/cache_put() on an uninitialized or already-freed svc_export pointer, corrupting export-cache refcounts and creating a use-after-free that can be leveraged for arbitrary kernel memory disclosure.\nI:H - Incorrect kref_put() on a dangling or garbage svc_export pointer is exploitable memory corruption that can lead to further heap manipulation and potential arbitrary kernel code execution, not merely a bounded error.\nA:H - Calling exp_put() on an invalid pointer reliably causes kernel oops/panic or premature export-cache destruction, producing high availability impact including NFS service disruption and possible full kernel crash."}]}],"providerMetadata":{"shortName":"Linux","orgId":"416baaa9-dc9f-4396-8d5f-8c081fb06d67","dateUpdated":"2026-08-17T04:50:50.328Z"},"cpeApplicability":[{"nodes":[{"operator":"OR","negate":false,"cpeMatch":[{"vulnerable":true,"criteria":"cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*","versionStartIncluding":"5.10.220","versionEndExcluding":"5.10.260"},{"vulnerable":true,"criteria":"cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*","versionStartIncluding":"5.15.154","versionEndExcluding":"5.15.211"},{"vulnerable":true,"criteria":"cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*","versionStartIncluding":"6.1","versionEndExcluding":"6.1.177"},{"vulnerable":true,"criteria":"cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*","versionStartIncluding":"6.1","versionEndExcluding":"6.6.144"},{"vulnerable":true,"criteria":"cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*","versionStartIncluding":"6.1","versionEndExcluding":"6.12.95"},{"vulnerable":true,"criteria":"cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*","versionStartIncluding":"6.1","versionEndExcluding":"6.18.38"},{"vulnerable":true,"criteria":"cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*","versionStartIncluding":"6.1","versionEndExcluding":"7.1.3"},{"vulnerable":true,"criteria":"cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*","versionStartIncluding":"6.1","versionEndExcluding":"7.2"}]}]}],"x_generator":{"engine":"bippy-1.2.0"}},"adp":[{"title":"CISA ADP Vulnrichment","metrics":[{"other":{"type":"ssvc","content":{"id":"CVE-2026-53398","role":"CISA Coordinator","options":[{"Exploitation":"none"},{"Automatable":"yes"},{"Technical Impact":"total"}],"version":"2.0.3","timestamp":"2026-10-16T15:30:25.764915Z"}}}],"problemTypes":[{"descriptions":[{"cweId":"CWE-665","lang":"en","type":"CWE","description":"CWE-665 Improper Initialization"}]}],"providerMetadata":{"shortName":"CISA-ADP","orgId":"134c704f-9b21-4f2e-91b3-4a467353bcc0","dateUpdated":"2026-10-19T20:07:46.561Z"}}]}}}