{"dataType":"CVE_RECORD","dataVersion":"5.2","cveMetadata":{"cveId":"CVE-2026-31674","assignerOrgId":"416baaa9-dc9f-4396-8d5f-8c081fb06d67","state":"PUBLISHED","assignerShortName":"Linux","dateReserved":"2026-03-09T15:48:24.130Z","datePublished":"2026-04-25T08:46:50.180Z","dateUpdated":"2026-09-08T08:48:03.642Z"},"containers":{"cna":{"providerMetadata":{"orgId":"416baaa9-dc9f-4396-8d5f-8c081fb06d67","shortName":"Linux","dateUpdated":"2026-08-05T12:24:21.417Z"},"descriptions":[{"lang":"en","value":"In the Linux kernel, the following vulnerability has been resolved:\n\nnetfilter: ip6t_rt: reject oversized addrnr in rt_mt6_check()\n\nReject rt match rules whose addrnr exceeds IP6T_RT_HOPS.\n\nrt_mt6() expects addrnr to stay within the bounds of rtinfo->addrs[].\nValidate addrnr during rule installation so malformed rules are rejected\nbefore the match logic can use an out-of-range value."}],"metrics":[{"cvssV3_1":{"version":"3.1","vectorString":"CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:N/A:H","baseScore":7.1,"baseSeverity":"HIGH"},"scenarios":[{"lang":"en","value":"AV:L - The vulnerable match is installed through the IPv6 iptables setsockopt path, so the attacker must execute local code to submit a malformed rule. Packets only trigger the bad read after that local rule installation step.\nAC:L - No race or external timing condition is required; the attacker controls the malformed `addrnr` value and can generate an IPv6 routing-header packet with enough addresses to reach the out-of-bounds access. The required netfilter match configuration is the affected component rather than an exploitation complexity barrier.\nPR:L - Rule replacement requires `CAP_NET_ADMIN`, but the check is against `sock_net(sk)->user_ns`, making it reachable to an unprivileged local user who can create a user and network namespace. This is Low rather than High under the kernel guidance.\nUI:N - After the attacker installs the malformed rule, triggering occurs by sending traffic through the affected netfilter hook. No victim user action is required.\nS:U - The bug is in kernel netfilter rule evaluation and impacts the same kernel security authority. It is not a VM escape, IOMMU bypass, or other cross-scope boundary violation.\nC:H - `addrnr` indexes beyond `rtinfo->addrs[]`, causing an out-of-bounds kernel memory read during packet matching. The overread can extend well beyond a few bytes, so confidentiality impact is High.\nI:N - The vulnerable operation is an out-of-bounds read used for address comparison, with no write or direct memory modification primitive. It does not by itself provide kernel memory corruption or control-flow modification.\nA:H - The out-of-bounds read can reach beyond the allocated xtables rule blob, especially with attacker-shaped tables and oversized routing-header address counts. Such kernel invalid memory access is capable of causing an oops or panic, so availability impact is High."}]}],"affected":[{"product":"Linux","vendor":"Linux","defaultStatus":"unaffected","repo":"https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git","programFiles":["net/ipv6/netfilter/ip6t_rt.c"],"versions":[{"version":"1da177e4c3f41524e886b7f1b8a0c1fc7321cac2","lessThan":"13e3e30ed3b5b67cc1db2bd58a5d09b0f07debfa","status":"affected","versionType":"git"},{"version":"1da177e4c3f41524e886b7f1b8a0c1fc7321cac2","lessThan":"af9b7e2b765966457f4ec23be5bd34a141f89574","status":"affected","versionType":"git"},{"version":"1da177e4c3f41524e886b7f1b8a0c1fc7321cac2","lessThan":"29ea965a1353bc8303877422f79c8211e9ba9c55","status":"affected","versionType":"git"},{"version":"1da177e4c3f41524e886b7f1b8a0c1fc7321cac2","lessThan":"c6a503a9f4debc654e3a6a7ca1f7fce6a9953c59","status":"affected","versionType":"git"},{"version":"1da177e4c3f41524e886b7f1b8a0c1fc7321cac2","lessThan":"ded71f5684df16fa645cca5bf4fe6b0cd8a46119","status":"affected","versionType":"git"},{"version":"1da177e4c3f41524e886b7f1b8a0c1fc7321cac2","lessThan":"d8795fde1f78669a87c87ac29fceab2f104daa8c","status":"affected","versionType":"git"},{"version":"1da177e4c3f41524e886b7f1b8a0c1fc7321cac2","lessThan":"a28ebf6f99de270d6338ccdc3b49f3e818f99b7b","status":"affected","versionType":"git"},{"version":"1da177e4c3f41524e886b7f1b8a0c1fc7321cac2","lessThan":"9d3f027327c2fa265f7f85ead41294792c3296ed","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/ipv6/netfilter/ip6t_rt.c"],"versions":[{"version":"2.6.12","status":"affected"},{"version":"0","lessThan":"2.6.12","status":"unaffected","versionType":"semver"},{"version":"5.10.253","lessThanOrEqual":"5.10.*","status":"unaffected","versionType":"semver"},{"version":"5.15.203","lessThanOrEqual":"5.15.*","status":"unaffected","versionType":"semver"},{"version":"6.1.168","lessThanOrEqual":"6.1.*","status":"unaffected","versionType":"semver"},{"version":"6.6.131","lessThanOrEqual":"6.6.*","status":"unaffected","versionType":"semver"},{"version":"6.12.80","lessThanOrEqual":"6.12.*","status":"unaffected","versionType":"semver"},{"version":"6.18.21","lessThanOrEqual":"6.18.*","status":"unaffected","versionType":"semver"},{"version":"6.19.11","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":"2.6.12","versionEndExcluding":"5.10.253"},{"vulnerable":true,"criteria":"cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*","versionStartIncluding":"2.6.12","versionEndExcluding":"5.15.203"},{"vulnerable":true,"criteria":"cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*","versionStartIncluding":"2.6.12","versionEndExcluding":"6.1.168"},{"vulnerable":true,"criteria":"cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*","versionStartIncluding":"2.6.12","versionEndExcluding":"6.6.131"},{"vulnerable":true,"criteria":"cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*","versionStartIncluding":"2.6.12","versionEndExcluding":"6.12.80"},{"vulnerable":true,"criteria":"cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*","versionStartIncluding":"2.6.12","versionEndExcluding":"6.18.21"},{"vulnerable":true,"criteria":"cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*","versionStartIncluding":"2.6.12","versionEndExcluding":"6.19.11"},{"vulnerable":true,"criteria":"cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*","versionStartIncluding":"2.6.12","versionEndExcluding":"7.0"}]}]}],"references":[{"url":"https://git.kernel.org/stable/c/13e3e30ed3b5b67cc1db2bd58a5d09b0f07debfa"},{"url":"https://git.kernel.org/stable/c/af9b7e2b765966457f4ec23be5bd34a141f89574"},{"url":"https://git.kernel.org/stable/c/29ea965a1353bc8303877422f79c8211e9ba9c55"},{"url":"https://git.kernel.org/stable/c/c6a503a9f4debc654e3a6a7ca1f7fce6a9953c59"},{"url":"https://git.kernel.org/stable/c/ded71f5684df16fa645cca5bf4fe6b0cd8a46119"},{"url":"https://git.kernel.org/stable/c/d8795fde1f78669a87c87ac29fceab2f104daa8c"},{"url":"https://git.kernel.org/stable/c/a28ebf6f99de270d6338ccdc3b49f3e818f99b7b"},{"url":"https://git.kernel.org/stable/c/9d3f027327c2fa265f7f85ead41294792c3296ed"}],"title":"netfilter: 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