{"api_version":"1","generated_at":"2026-04-25T13:02:03+00:00","cve":"CVE-2026-31684","urls":{"html":"https://cve.report/CVE-2026-31684","api":"https://cve.report/api/cve/CVE-2026-31684.json","docs":"https://cve.report/api","cve_org":"https://www.cve.org/CVERecord?id=CVE-2026-31684","nvd":"https://nvd.nist.gov/vuln/detail/CVE-2026-31684"},"summary":{"title":"net: sched: act_csum: validate nested VLAN headers","description":"In the Linux kernel, the following vulnerability has been resolved:\n\nnet: sched: act_csum: validate nested VLAN headers\n\ntcf_csum_act() walks nested VLAN headers directly from skb->data when an\nskb still carries in-payload VLAN tags. The current code reads\nvlan->h_vlan_encapsulated_proto and then pulls VLAN_HLEN bytes without\nfirst ensuring that the full VLAN header is present in the linear area.\n\nIf only part of an inner VLAN header is linearized, accessing\nh_vlan_encapsulated_proto reads past the linear area, and the following\nskb_pull(VLAN_HLEN) may violate skb invariants.\n\nFix this by requiring pskb_may_pull(skb, VLAN_HLEN) before accessing and\npulling each nested VLAN header. If the header still is not fully\navailable, drop the packet through the existing error path.","state":"PUBLISHED","assigner":"Linux","published_at":"2026-04-25 09:16:02","updated_at":"2026-04-25 09:16:02"},"problem_types":[],"metrics":[],"references":[{"url":"https://git.kernel.org/stable/c/3d165d975305cf76ff0b10a3c798fb31e5f5f9a5","name":"https://git.kernel.org/stable/c/3d165d975305cf76ff0b10a3c798fb31e5f5f9a5","refsource":"416baaa9-dc9f-4396-8d5f-8c081fb06d67","tags":[],"title":"","mime":"","httpstatus":"","archivestatus":"0"},{"url":"https://git.kernel.org/stable/c/ec4930979b3f7bbeb7af5744599fc6603a4dba62","name":"https://git.kernel.org/stable/c/ec4930979b3f7bbeb7af5744599fc6603a4dba62","refsource":"416baaa9-dc9f-4396-8d5f-8c081fb06d67","tags":[],"title":"","mime":"","httpstatus":"","archivestatus":"0"},{"url":"https://git.kernel.org/stable/c/c842743d073bdd683606cb414eb0ca84465dd834","name":"https://git.kernel.org/stable/c/c842743d073bdd683606cb414eb0ca84465dd834","refsource":"416baaa9-dc9f-4396-8d5f-8c081fb06d67","tags":[],"title":"","mime":"","httpstatus":"","archivestatus":"0"},{"url":"https://git.kernel.org/stable/c/a69738efea0996d05a3c7d2178551b891744df1b","name":"https://git.kernel.org/stable/c/a69738efea0996d05a3c7d2178551b891744df1b","refsource":"416baaa9-dc9f-4396-8d5f-8c081fb06d67","tags":[],"title":"","mime":"","httpstatus":"","archivestatus":"0"},{"url":"https://www.cve.org/CVERecord?id=CVE-2026-31684","name":"CVE Program record","refsource":"CVE.ORG","tags":["canonical"]},{"url":"https://nvd.nist.gov/vuln/detail/CVE-2026-31684","name":"NVD vulnerability detail","refsource":"NVD","tags":["canonical","analysis"]}],"affected":[{"source":"CNA","vendor":"Linux","product":"Linux","version":"affected 2ecba2d1e45b24620a7c3df9531895cf68d5dec6 a69738efea0996d05a3c7d2178551b891744df1b git","platforms":[]},{"source":"CNA","vendor":"Linux","product":"Linux","version":"affected 2ecba2d1e45b24620a7c3df9531895cf68d5dec6 ec4930979b3f7bbeb7af5744599fc6603a4dba62 git","platforms":[]},{"source":"CNA","vendor":"Linux","product":"Linux","version":"affected 2ecba2d1e45b24620a7c3df9531895cf68d5dec6 3d165d975305cf76ff0b10a3c798fb31e5f5f9a5 git","platforms":[]},{"source":"CNA","vendor":"Linux","product":"Linux","version":"affected 2ecba2d1e45b24620a7c3df9531895cf68d5dec6 c842743d073bdd683606cb414eb0ca84465dd834 git","platforms":[]},{"source":"CNA","vendor":"Linux","product":"Linux","version":"affected 3764bfae5056e95617b6ee074129297e11710886 git","platforms":[]},{"source":"CNA","vendor":"Linux","product":"Linux","version":"affected 5.1","platforms":[]},{"source":"CNA","vendor":"Linux","product":"Linux","version":"unaffected 5.1 semver","platforms":[]},{"source":"CNA","vendor":"Linux","product":"Linux","version":"unaffected 6.12.83 6.12.* semver","platforms":[]},{"source":"CNA","vendor":"Linux","product":"Linux","version":"unaffected 6.18.24 6.18.* semver","platforms":[]},{"source":"CNA","vendor":"Linux","product":"Linux","version":"unaffected 6.19.14 6.19.* semver","platforms":[]},{"source":"CNA","vendor":"Linux","product":"Linux","version":"unaffected 7.0 * 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":["net/sched/act_csum.c"],"repo":"https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git","vendor":"Linux","versions":[{"lessThan":"a69738efea0996d05a3c7d2178551b891744df1b","status":"affected","version":"2ecba2d1e45b24620a7c3df9531895cf68d5dec6","versionType":"git"},{"lessThan":"ec4930979b3f7bbeb7af5744599fc6603a4dba62","status":"affected","version":"2ecba2d1e45b24620a7c3df9531895cf68d5dec6","versionType":"git"},{"lessThan":"3d165d975305cf76ff0b10a3c798fb31e5f5f9a5","status":"affected","version":"2ecba2d1e45b24620a7c3df9531895cf68d5dec6","versionType":"git"},{"lessThan":"c842743d073bdd683606cb414eb0ca84465dd834","status":"affected","version":"2ecba2d1e45b24620a7c3df9531895cf68d5dec6","versionType":"git"},{"status":"affected","version":"3764bfae5056e95617b6ee074129297e11710886","versionType":"git"}]},{"defaultStatus":"affected","product":"Linux","programFiles":["net/sched/act_csum.c"],"repo":"https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git","vendor":"Linux","versions":[{"status":"affected","version":"5.1"},{"lessThan":"5.1","status":"unaffected","version":"0","versionType":"semver"},{"lessThanOrEqual":"6.12.*","status":"unaffected","version":"6.12.83","versionType":"semver"},{"lessThanOrEqual":"6.18.*","status":"unaffected","version":"6.18.24","versionType":"semver"},{"lessThanOrEqual":"6.19.*","status":"unaffected","version":"6.19.14","versionType":"semver"},{"lessThanOrEqual":"*","status":"unaffected","version":"7.0","versionType":"original_commit_for_fix"}]}],"cpeApplicability":[{"nodes":[{"cpeMatch":[{"criteria":"cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*","versionEndExcluding":"6.12.83","versionStartIncluding":"5.1","vulnerable":true},{"criteria":"cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*","versionEndExcluding":"6.18.24","versionStartIncluding":"5.1","vulnerable":true},{"criteria":"cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*","versionEndExcluding":"6.19.14","versionStartIncluding":"5.1","vulnerable":true},{"criteria":"cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*","versionEndExcluding":"7.0","versionStartIncluding":"5.1","vulnerable":true},{"criteria":"cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*","versionStartIncluding":"4.19.99","vulnerable":true}],"negate":false,"operator":"OR"}]}],"descriptions":[{"lang":"en","value":"In the Linux kernel, the following vulnerability has been resolved:\n\nnet: sched: act_csum: validate nested VLAN headers\n\ntcf_csum_act() walks nested VLAN headers directly from skb->data when an\nskb still carries in-payload VLAN tags. The current code reads\nvlan->h_vlan_encapsulated_proto and then pulls VLAN_HLEN bytes without\nfirst ensuring that the full VLAN header is present in the linear area.\n\nIf only part of an inner VLAN header is linearized, accessing\nh_vlan_encapsulated_proto reads past the linear area, and the following\nskb_pull(VLAN_HLEN) may violate skb invariants.\n\nFix this by requiring pskb_may_pull(skb, VLAN_HLEN) before accessing and\npulling each nested VLAN header. If the header still is not fully\navailable, drop the packet through the existing error path."}],"providerMetadata":{"dateUpdated":"2026-04-25T08:47:01.555Z","orgId":"416baaa9-dc9f-4396-8d5f-8c081fb06d67","shortName":"Linux"},"references":[{"url":"https://git.kernel.org/stable/c/a69738efea0996d05a3c7d2178551b891744df1b"},{"url":"https://git.kernel.org/stable/c/ec4930979b3f7bbeb7af5744599fc6603a4dba62"},{"url":"https://git.kernel.org/stable/c/3d165d975305cf76ff0b10a3c798fb31e5f5f9a5"},{"url":"https://git.kernel.org/stable/c/c842743d073bdd683606cb414eb0ca84465dd834"}],"title":"net: sched: act_csum: validate nested VLAN headers","x_generator":{"engine":"bippy-1.2.0"}}},"cveMetadata":{"assignerOrgId":"416baaa9-dc9f-4396-8d5f-8c081fb06d67","assignerShortName":"Linux","cveId":"CVE-2026-31684","datePublished":"2026-04-25T08:47:01.555Z","dateReserved":"2026-03-09T15:48:24.130Z","dateUpdated":"2026-04-25T08:47:01.555Z","state":"PUBLISHED"},"dataType":"CVE_RECORD","dataVersion":"5.2"},"nvd":{"publishedDate":"2026-04-25 09:16:02","lastModifiedDate":"2026-04-25 09:16:02","problem_types":[],"metrics":[],"configurations":[]},"legacy_mitre":{"record":{"CveYear":"2026","CveId":"31684","Ordinal":"1","Title":"net: sched: act_csum: validate nested VLAN headers","CVE":"CVE-2026-31684","Year":"2026"},"notes":[{"CveYear":"2026","CveId":"31684","Ordinal":"1","NoteData":"In the Linux kernel, the following vulnerability has been resolved:\n\nnet: sched: act_csum: validate nested VLAN headers\n\ntcf_csum_act() walks nested VLAN headers directly from skb->data when an\nskb still carries in-payload VLAN tags. The current code reads\nvlan->h_vlan_encapsulated_proto and then pulls VLAN_HLEN bytes without\nfirst ensuring that the full VLAN header is present in the linear area.\n\nIf only part of an inner VLAN header is linearized, accessing\nh_vlan_encapsulated_proto reads past the linear area, and the following\nskb_pull(VLAN_HLEN) may violate skb invariants.\n\nFix this by requiring pskb_may_pull(skb, VLAN_HLEN) before accessing and\npulling each nested VLAN header. If the header still is not fully\navailable, drop the packet through the existing error path.","Type":"Description","Title":"net: sched: act_csum: validate nested VLAN headers"}]}}}