{"dataType":"CVE_RECORD","dataVersion":"5.2","cveMetadata":{"cveId":"CVE-2026-31684","assignerOrgId":"416baaa9-dc9f-4396-8d5f-8c081fb06d67","state":"PUBLISHED","assignerShortName":"Linux","dateReserved":"2026-03-09T15:48:24.130Z","datePublished":"2026-04-25T08:47:01.555Z","dateUpdated":"2026-05-11T22:13:38.439Z"},"containers":{"cna":{"providerMetadata":{"orgId":"416baaa9-dc9f-4396-8d5f-8c081fb06d67","shortName":"Linux","dateUpdated":"2026-05-11T22:13:38.439Z"},"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."}],"affected":[{"product":"Linux","vendor":"Linux","defaultStatus":"unaffected","repo":"https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git","programFiles":["net/sched/act_csum.c"],"versions":[{"version":"2ecba2d1e45b24620a7c3df9531895cf68d5dec6","lessThan":"eb3765b90eb8f2a3d6310a80c14a9e57ec4267a2","status":"affected","versionType":"git"},{"version":"2ecba2d1e45b24620a7c3df9531895cf68d5dec6","lessThan":"a69738efea0996d05a3c7d2178551b891744df1b","status":"affected","versionType":"git"},{"version":"2ecba2d1e45b24620a7c3df9531895cf68d5dec6","lessThan":"ec4930979b3f7bbeb7af5744599fc6603a4dba62","status":"affected","versionType":"git"},{"version":"2ecba2d1e45b24620a7c3df9531895cf68d5dec6","lessThan":"3d165d975305cf76ff0b10a3c798fb31e5f5f9a5","status":"affected","versionType":"git"},{"version":"2ecba2d1e45b24620a7c3df9531895cf68d5dec6","lessThan":"c842743d073bdd683606cb414eb0ca84465dd834","status":"affected","versionType":"git"},{"version":"3764bfae5056e95617b6ee074129297e11710886","status":"affected","versionType":"git"}]},{"product":"Linux","vendor":"Linux","defaultStatus":"affected","repo":"https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git","programFiles":["net/sched/act_csum.c"],"versions":[{"version":"5.1","status":"affected"},{"version":"0","lessThan":"5.1","status":"unaffected","versionType":"semver"},{"version":"6.6.136","lessThanOrEqual":"6.6.*","status":"unaffected","versionType":"semver"},{"version":"6.12.83","lessThanOrEqual":"6.12.*","status":"unaffected","versionType":"semver"},{"version":"6.18.24","lessThanOrEqual":"6.18.*","status":"unaffected","versionType":"semver"},{"version":"6.19.14","lessThanOrEqual":"6.19.*","status":"unaffected","versionType":"semver"},{"version":"7.0","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":"5.1","versionEndExcluding":"6.6.136"},{"vulnerable":true,"criteria":"cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*","versionStartIncluding":"5.1","versionEndExcluding":"6.12.83"},{"vulnerable":true,"criteria":"cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*","versionStartIncluding":"5.1","versionEndExcluding":"6.18.24"},{"vulnerable":true,"criteria":"cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*","versionStartIncluding":"5.1","versionEndExcluding":"6.19.14"},{"vulnerable":true,"criteria":"cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*","versionStartIncluding":"5.1","versionEndExcluding":"7.0"},{"vulnerable":true,"criteria":"cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*","versionStartIncluding":"4.19.99"}]}]}],"references":[{"url":"https://git.kernel.org/stable/c/eb3765b90eb8f2a3d6310a80c14a9e57ec4267a2"},{"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"}}}}