{"id":"CVE-2026-80792","title":"ipv6: fix use-after-free in ip6_finish_output2()","summary":"In the Linux kernel, the following vulnerability has been resolved:\n\nipv6: fix use-after-free in ip6_finish_output2()\n\nip6_finish_output2() caches a pointer to the IPv6 destination\naddress (daddr) before invoking lwtunnel_xmit().  The LW…","severity":"none","vendor":"Linux","product":"Linux","affected":["Linux >= 4132c4ad00ddbf3a175ea0d2c775b662a32f4c85 < 75e0a544ebe9af663ef53ca21e9e9185c51fb54a","Linux >= e415ed3a4b8b246ee5e9d109ff5153efcf96b9f2 < c95f01b78266828a57060d754fcbfc92123a98ed","Linux >= e415ed3a4b8b246ee5e9d109ff5153efcf96b9f2 < d960881b9312e781a3429aabceb223ce6b7c882f","Linux >= e415ed3a4b8b246ee5e9d109ff5153efcf96b9f2 < 087ee0d914aaae929f1660c9ca878e367655ba1a","Linux >= e415ed3a4b8b246ee5e9d109ff5153efcf96b9f2 < 3c770ac4e6f07af7c7b40c474a3efc61ffed7862","Linux >= e415ed3a4b8b246ee5e9d109ff5153efcf96b9f2 < 3dc98e5fe82d069dd29b124ffbdb679331dfea43","Linux >= e415ed3a4b8b246ee5e9d109ff5153efcf96b9f2 < 99219c82804f266189388e8bf1cf5135d10d5515","Linux >= e415ed3a4b8b246ee5e9d109ff5153efcf96b9f2 < 73a187384a8c8b983c7fea046d716b6752a1e7a3","Linux >= e415ed3a4b8b246ee5e9d109ff5153efcf96b9f2 < d0d48d999b0eee6bb176ef4e39d9be868fa80f7e","Linux 1598154fd28ffa4a55beae1970475fd6776554b6","Linux >= 5.10.233 < 5.10.267","Linux >= 5.4.289 < 5.5","Linux 5.15"],"published":"2026-09-04","updated":"2026-10-19","sourceUpdated":"2026-10-19T08:43:45.535Z","source":"CVEORG","sourceUrl":"https://www.cve.org/CVERecord?id=CVE-2026-80792","references":[{"url":"https://git.kernel.org/stable/c/75e0a544ebe9af663ef53ca21e9e9185c51fb54a"},{"url":"https://git.kernel.org/stable/c/c95f01b78266828a57060d754fcbfc92123a98ed"},{"url":"https://git.kernel.org/stable/c/d960881b9312e781a3429aabceb223ce6b7c882f"},{"url":"https://git.kernel.org/stable/c/087ee0d914aaae929f1660c9ca878e367655ba1a"},{"url":"https://git.kernel.org/stable/c/3c770ac4e6f07af7c7b40c474a3efc61ffed7862"},{"url":"https://git.kernel.org/stable/c/3dc98e5fe82d069dd29b124ffbdb679331dfea43"},{"url":"https://git.kernel.org/stable/c/99219c82804f266189388e8bf1cf5135d10d5515"},{"url":"https://git.kernel.org/stable/c/73a187384a8c8b983c7fea046d716b6752a1e7a3"},{"url":"https://git.kernel.org/stable/c/d0d48d999b0eee6bb176ef4e39d9be868fa80f7e"}],"tags":["cve.org"],"epss":0.00195,"epssPercentile":0.08585,"ingestedAt":"2026-10-19T09:16:01.530Z","slug":"CVE-2026-80792","body":"## Overview\n\nIn the Linux kernel, the following vulnerability has been resolved:\n\nipv6: fix use-after-free in ip6_finish_output2()\n\nip6_finish_output2() caches a pointer to the IPv6 destination\naddress (daddr) before invoking lwtunnel_xmit().  The LWT-BPF\ntransmit path or other encapsulation operations within\nlwtunnel_xmit() can reallocate the skb head, freeing the memory\nthat daddr points to.  When lwtunnel_xmit() returns\nLWTUNNEL_XMIT_CONTINUE, the function continues to use the stale\ndaddr pointer to compute the nexthop and to look up or create the\nneighbour entry.  This results in a use-after-free read, which can\nleak sensitive kernel data, pollute the neighbour table with\narbitrary values, misdirect traffic, or crash the system.\n\nFix this by re-fetching the IPv6 header and the destination\naddress pointer after lwtunnel_xmit() returns\nLWTUNNEL_XMIT_CONTINUE, ensuring that the subsequent nexthop\ncomputation and neighbour lookup operate on valid memory.\n\n## Affected\n\n- `Linux >= 4132c4ad00ddbf3a175ea0d2c775b662a32f4c85 < 75e0a544ebe9af663ef53ca21e9e9185c51fb54a`\n- `Linux >= e415ed3a4b8b246ee5e9d109ff5153efcf96b9f2 < c95f01b78266828a57060d754fcbfc92123a98ed`\n- `Linux >= e415ed3a4b8b246ee5e9d109ff5153efcf96b9f2 < d960881b9312e781a3429aabceb223ce6b7c882f`\n- `Linux >= e415ed3a4b8b246ee5e9d109ff5153efcf96b9f2 < 087ee0d914aaae929f1660c9ca878e367655ba1a`\n- `Linux >= e415ed3a4b8b246ee5e9d109ff5153efcf96b9f2 < 3c770ac4e6f07af7c7b40c474a3efc61ffed7862`\n- `Linux >= e415ed3a4b8b246ee5e9d109ff5153efcf96b9f2 < 3dc98e5fe82d069dd29b124ffbdb679331dfea43`\n- `Linux >= e415ed3a4b8b246ee5e9d109ff5153efcf96b9f2 < 99219c82804f266189388e8bf1cf5135d10d5515`\n- `Linux >= e415ed3a4b8b246ee5e9d109ff5153efcf96b9f2 < 73a187384a8c8b983c7fea046d716b6752a1e7a3`\n- `Linux >= e415ed3a4b8b246ee5e9d109ff5153efcf96b9f2 < d0d48d999b0eee6bb176ef4e39d9be868fa80f7e`\n- `Linux 1598154fd28ffa4a55beae1970475fd6776554b6`\n- `Linux >= 5.10.233 < 5.10.267`\n- `Linux >= 5.4.289 < 5.5`\n- `Linux 5.15`\n\n## Remediation\n\nRefer to the linked advisories for vendor-supplied fixes and affected version ranges.","depth":"sunlit","depthScore":3,"depthScoreParts":{"impact":2.8,"likelihood":0,"exploitation":0,"ransomware":0},"changes":[]}