{"id":"CVE-2026-74597","aliases":[],"url":"https://o3.security/vulnerability/CVE-2026-74597","summary":"ip6_tunnel: clear skb2->cb[] in ip6ip6_err()","details":"In the Linux kernel, the following vulnerability has been resolved:\n\nip6_tunnel: clear skb2->cb[] in ip6ip6_err()\n\nip6ip6_err() clones an outer IPv6 ICMP error skb, pulls it to the\nquoted inner IPv6 packet, and then passes the clone to icmpv6_send().\nThe clone still carries the outer packet's inet6_skb_parm in skb->cb.\n\nIf the outer packet had a Home Address Option, IP6CB(skb2)->dsthao\nremains non-zero after skb_pull(). icmpv6_send() later calls\nmip6_addr_swap(), which uses that stale dsthao offset against the quoted\ninner packet. A malformed inner destination-options header can then make\nthe HAO lookup and address swap run past the end of the quoted packet\nand corrupt skb_shared_info.\n\nClear skb2->cb[] before pulling the quoted inner IPv6 packet so the\nreply path does not reuse metadata left by the outer IPv6 stack.","published":"2026-08-22T15:31:47.120Z","modified":"2026-08-24T11:46:57.167522072Z","cvss":null,"epss":null,"cisaKev":null,"exploitsKnown":null,"affectedPackages":[{"ecosystem":"Linux","name":"Kernel","fixedVersion":"5.10.265"}],"fix":null,"references":[{"type":"WEB","url":"https://git.kernel.org/stable/c/0dadb0620ab65949a8bc2439dd28ea3c942fe87d"},{"type":"WEB","url":"https://git.kernel.org/stable/c/44fe898df302e91c5ee5acbc71ffa74e78e6c183"},{"type":"WEB","url":"https://git.kernel.org/stable/c/484134e1eb07d700a73b1e4bbf3fb503e299be60"},{"type":"WEB","url":"https://git.kernel.org/stable/c/4eb15c465337b18f44716c499cd6ad63eee0ad54"},{"type":"WEB","url":"https://git.kernel.org/stable/c/64e41736a26f37ab6215bc2e6df125df05aceb08"},{"type":"WEB","url":"https://git.kernel.org/stable/c/b6816536a2990c0db44a26130a03e40b441e829b"},{"type":"WEB","url":"https://git.kernel.org/stable/c/f803c086399da277b5d0ff36a107d0f162751800"},{"type":"WEB","url":"https://git.kernel.org/stable/c/fbf40faa0414b753212494ad197542002e66ed9e"},{"type":"ADVISORY","url":"https://github.com/CVEProject/cvelistV5/tree/main/cves/2026/74xxx/CVE-2026-74597.json"},{"type":"ADVISORY","url":"https://nvd.nist.gov/vuln/detail/CVE-2026-74597"},{"type":"PACKAGE","url":"https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git"}],"provenance":{"sources":["OSV.dev","FIRST.org (EPSS)"],"lastVerified":"2026-08-24T11:46:57.167522072Z"}}