{"api_version":"1","generated_at":"2026-09-11T22:32:24+00:00","cve":"CVE-2026-89690","urls":{"html":"https://cve.report/CVE-2026-89690","api":"https://cve.report/api/cve/CVE-2026-89690.json","docs":"https://cve.report/api","cve_org":"https://www.cve.org/CVERecord?id=CVE-2026-89690","nvd":"https://nvd.nist.gov/vuln/detail/CVE-2026-89690"},"summary":{"title":"nfsd: defer vfree of compound ops to fix rpc_status UAF","description":"In the Linux kernel, the following vulnerability has been resolved:\n\nnfsd: defer vfree of compound ops to fix rpc_status UAF\n\nThe rpc_status netlink dumpit walks every in-flight svc_rqst under\nrcu_read_lock and, for NFSv4 requests, reads opnums out of\nargs->ops[]. But args->ops is a separate vmalloc buffer freed\nsynchronously by vfree() in nfsd4_release_compoundargs() at the end\nof every compound. The dumpit's rcu_read_lock pins the svc_rqst\nstruct itself (freed via kfree_rcu), but nothing defers the vfree\nof the ops buffer across the RCU grace period. A concurrent compound\ncompletion can therefore free the buffer while the dumpit is reading\nit — a use-after-free on vmalloc memory.\n\nThe trailing seqcount recheck (smp_load_acquire of rq_status_counter)\ncannot undo a load that already retired against freed memory.\n\nFix by replacing vfree(args->ops) with kvfree_rcu_mightsleep(), which\ndefers the free until after an RCU grace period. This makes the\nexisting rcu_read_lock in the dumpit sufficient to protect the read.\nThe tradeoff is that completed compound ops buffers (up to\n200 * sizeof(struct nfsd4_op)) persist in memory slightly longer,\nacross one grace period, before being reclaimed.","state":"PUBLISHED","assigner":"Linux","published_at":"2026-09-11 20:19:56","updated_at":"2026-09-11 20:19:56"},"problem_types":[],"metrics":[],"references":[{"url":"https://git.kernel.org/stable/c/19413ccc45070a7270b9e25c2a258daf7f91de42","name":"https://git.kernel.org/stable/c/19413ccc45070a7270b9e25c2a258daf7f91de42","refsource":"416baaa9-dc9f-4396-8d5f-8c081fb06d67","tags":[],"title":"","mime":"","httpstatus":"","archivestatus":"0"},{"url":"https://git.kernel.org/stable/c/fca26a3fc19ed02278aa2a150af82d43db0302cb","name":"https://git.kernel.org/stable/c/fca26a3fc19ed02278aa2a150af82d43db0302cb","refsource":"416baaa9-dc9f-4396-8d5f-8c081fb06d67","tags":[],"title":"","mime":"","httpstatus":"","archivestatus":"0"},{"url":"https://git.kernel.org/stable/c/6703199f4d7e7f37d6a726a849eb358e8fae72fb","name":"https://git.kernel.org/stable/c/6703199f4d7e7f37d6a726a849eb358e8fae72fb","refsource":"416baaa9-dc9f-4396-8d5f-8c081fb06d67","tags":[],"title":"","mime":"","httpstatus":"","archivestatus":"0"},{"url":"https://git.kernel.org/stable/c/48f72aff24f7a7329209dc6cbc27c869f3e3595c","name":"https://git.kernel.org/stable/c/48f72aff24f7a7329209dc6cbc27c869f3e3595c","refsource":"416baaa9-dc9f-4396-8d5f-8c081fb06d67","tags":[],"title":"","mime":"","httpstatus":"","archivestatus":"0"},{"url":"https://www.cve.org/CVERecord?id=CVE-2026-89690","name":"CVE Program record","refsource":"CVE.ORG","tags":["canonical"]},{"url":"https://nvd.nist.gov/vuln/detail/CVE-2026-89690","name":"NVD vulnerability detail","refsource":"NVD","tags":["canonical","analysis"]}],"affected":[{"source":"CNA","vendor":"Linux","product":"Linux","version":"affected bd9d6a3efa9709e653aafbeb859289feccb8e70c 48f72aff24f7a7329209dc6cbc27c869f3e3595c git","platforms":[]},{"source":"CNA","vendor":"Linux","product":"Linux","version":"affected bd9d6a3efa9709e653aafbeb859289feccb8e70c 6703199f4d7e7f37d6a726a849eb358e8fae72fb git","platforms":[]},{"source":"CNA","vendor":"Linux","product":"Linux","version":"affected bd9d6a3efa9709e653aafbeb859289feccb8e70c 19413ccc45070a7270b9e25c2a258daf7f91de42 git","platforms":[]},{"source":"CNA","vendor":"Linux","product":"Linux","version":"affected bd9d6a3efa9709e653aafbeb859289feccb8e70c fca26a3fc19ed02278aa2a150af82d43db0302cb git","platforms":[]},{"source":"CNA","vendor":"Linux","product":"Linux","version":"affected 6.7","platforms":[]},{"source":"CNA","vendor":"Linux","product":"Linux","version":"unaffected 6.7 semver","platforms":[]},{"source":"CNA","vendor":"Linux","product":"Linux","version":"unaffected 6.12.109 6.12.* semver","platforms":[]},{"source":"CNA","vendor":"Linux","product":"Linux","version":"unaffected 6.18.50 6.18.* semver","platforms":[]},{"source":"CNA","vendor":"Linux","product":"Linux","version":"unaffected 7.2.4 7.2.* semver","platforms":[]},{"source":"CNA","vendor":"Linux","product":"Linux","version":"unaffected 7.3-rc1 * original_commit_for_fix","platforms":[]}],"timeline":[],"solutions":[],"workarounds":[],"exploits":[],"credits":[],"nvd_cpes":[],"vendor_comments":[],"enrichments":{"kev":null,"epss":null,"legacy_qids":[]},"source_records":{"cve_program":{"containers":{"cna":{"affected":[{"defaultStatus":"unaffected","product":"Linux","programFiles":["fs/nfsd/nfs4xdr.c"],"repo":"https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git","vendor":"Linux","versions":[{"lessThan":"48f72aff24f7a7329209dc6cbc27c869f3e3595c","status":"affected","version":"bd9d6a3efa9709e653aafbeb859289feccb8e70c","versionType":"git"},{"lessThan":"6703199f4d7e7f37d6a726a849eb358e8fae72fb","status":"affected","version":"bd9d6a3efa9709e653aafbeb859289feccb8e70c","versionType":"git"},{"lessThan":"19413ccc45070a7270b9e25c2a258daf7f91de42","status":"affected","version":"bd9d6a3efa9709e653aafbeb859289feccb8e70c","versionType":"git"},{"lessThan":"fca26a3fc19ed02278aa2a150af82d43db0302cb","status":"affected","version":"bd9d6a3efa9709e653aafbeb859289feccb8e70c","versionType":"git"}]},{"defaultStatus":"affected","product":"Linux","programFiles":["fs/nfsd/nfs4xdr.c"],"repo":"https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git","vendor":"Linux","versions":[{"status":"affected","version":"6.7"},{"lessThan":"6.7","status":"unaffected","version":"0","versionType":"semver"},{"lessThanOrEqual":"6.12.*","status":"unaffected","version":"6.12.109","versionType":"semver"},{"lessThanOrEqual":"6.18.*","status":"unaffected","version":"6.18.50","versionType":"semver"},{"lessThanOrEqual":"7.2.*","status":"unaffected","version":"7.2.4","versionType":"semver"},{"lessThanOrEqual":"*","status":"unaffected","version":"7.3-rc1","versionType":"original_commit_for_fix"}]}],"cpeApplicability":[{"nodes":[{"cpeMatch":[{"criteria":"cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*","versionEndExcluding":"6.12.109","versionStartIncluding":"6.7","vulnerable":true},{"criteria":"cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*","versionEndExcluding":"6.18.50","versionStartIncluding":"6.7","vulnerable":true},{"criteria":"cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*","versionEndExcluding":"7.2.4","versionStartIncluding":"6.7","vulnerable":true},{"criteria":"cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*","versionEndExcluding":"7.3-rc1","versionStartIncluding":"6.7","vulnerable":true}],"negate":false,"operator":"OR"}]}],"descriptions":[{"lang":"en","value":"In the Linux kernel, the following vulnerability has been resolved:\n\nnfsd: defer vfree of compound ops to fix rpc_status UAF\n\nThe rpc_status netlink dumpit walks every in-flight svc_rqst under\nrcu_read_lock and, for NFSv4 requests, reads opnums out of\nargs->ops[]. But args->ops is a separate vmalloc buffer freed\nsynchronously by vfree() in nfsd4_release_compoundargs() at the end\nof every compound. The dumpit's rcu_read_lock pins the svc_rqst\nstruct itself (freed via kfree_rcu), but nothing defers the vfree\nof the ops buffer across the RCU grace period. A concurrent compound\ncompletion can therefore free the buffer while the dumpit is reading\nit — a use-after-free on vmalloc memory.\n\nThe trailing seqcount recheck (smp_load_acquire of rq_status_counter)\ncannot undo a load that already retired against freed memory.\n\nFix by replacing vfree(args->ops) with kvfree_rcu_mightsleep(), which\ndefers the free until after an RCU grace period. This makes the\nexisting rcu_read_lock in the dumpit sufficient to protect the read.\nThe tradeoff is that completed compound ops buffers (up to\n200 * sizeof(struct nfsd4_op)) persist in memory slightly longer,\nacross one grace period, before being reclaimed."}],"providerMetadata":{"dateUpdated":"2026-09-11T19:46:10.632Z","orgId":"416baaa9-dc9f-4396-8d5f-8c081fb06d67","shortName":"Linux"},"references":[{"url":"https://git.kernel.org/stable/c/48f72aff24f7a7329209dc6cbc27c869f3e3595c"},{"url":"https://git.kernel.org/stable/c/6703199f4d7e7f37d6a726a849eb358e8fae72fb"},{"url":"https://git.kernel.org/stable/c/19413ccc45070a7270b9e25c2a258daf7f91de42"},{"url":"https://git.kernel.org/stable/c/fca26a3fc19ed02278aa2a150af82d43db0302cb"}],"title":"nfsd: defer vfree of compound ops to fix rpc_status UAF","x_generator":{"engine":"bippy-1.2.0"}}},"cveMetadata":{"assignerOrgId":"416baaa9-dc9f-4396-8d5f-8c081fb06d67","assignerShortName":"Linux","cveId":"CVE-2026-89690","datePublished":"2026-09-11T19:46:10.632Z","dateReserved":"2026-09-11T19:38:34.749Z","dateUpdated":"2026-09-11T19:46:10.632Z","state":"PUBLISHED"},"dataType":"CVE_RECORD","dataVersion":"5.2"},"nvd":{"publishedDate":"2026-09-11 20:19:56","lastModifiedDate":"2026-09-11 20:19:56","problem_types":[],"metrics":[],"configurations":[]},"legacy_mitre":{"record":{"CveYear":"2026","CveId":"89690","Ordinal":"1","Title":"nfsd: defer vfree of compound ops to fix rpc_status UAF","CVE":"CVE-2026-89690","Year":"2026"},"notes":[{"CveYear":"2026","CveId":"89690","Ordinal":"1","NoteData":"In the Linux kernel, the following vulnerability has been resolved:\n\nnfsd: defer vfree of compound ops to fix rpc_status UAF\n\nThe rpc_status netlink dumpit walks every in-flight svc_rqst under\nrcu_read_lock and, for NFSv4 requests, reads opnums out of\nargs->ops[]. But args->ops is a separate vmalloc buffer freed\nsynchronously by vfree() in nfsd4_release_compoundargs() at the end\nof every compound. The dumpit's rcu_read_lock pins the svc_rqst\nstruct itself (freed via kfree_rcu), but nothing defers the vfree\nof the ops buffer across the RCU grace period. A concurrent compound\ncompletion can therefore free the buffer while the dumpit is reading\nit — a use-after-free on vmalloc memory.\n\nThe trailing seqcount recheck (smp_load_acquire of rq_status_counter)\ncannot undo a load that already retired against freed memory.\n\nFix by replacing vfree(args->ops) with kvfree_rcu_mightsleep(), which\ndefers the free until after an RCU grace period. This makes the\nexisting rcu_read_lock in the dumpit sufficient to protect the read.\nThe tradeoff is that completed compound ops buffers (up to\n200 * sizeof(struct nfsd4_op)) persist in memory slightly longer,\nacross one grace period, before being reclaimed.","Type":"Description","Title":"nfsd: defer vfree of compound ops to fix rpc_status UAF"}]}}}