CVE-2026-74597
N/AIn the Linux kernel, the following vulnerability has been resolved: ip6_tunnel: clear skb2->cb[] in ip6ip6_err() ip6ip6_err() clones an outer IPv6 ICMP error skb, pulls it to the quoted inner IPv6 packet, and then passes the clone to icmpv6_send(). The clone still carries the outer packet's inet6_skb_parm in skb->cb. If the outer packet had a Home Address Option, IP6CB(skb2)->dsthao remains non-zero after skb_pull(). icmpv6_send() later calls mip6_addr_swap(), which uses that stale dsthao offset against the quoted inner packet. A malformed inner destination-options header can then make the HAO lookup and address swap run past the end of the quoted packet and corrupt skb_shared_info. Clear skb2->cb[] before pulling the quoted inner IPv6 packet so the reply path does not reuse metadata left by the outer IPv6 stack.
No known exploitation, public exploit, or elevated probability at this time. Track for changes.
Exploitation likelihood
—EPSS not yet scored
Impact if exploited
—CVSS · not scored
- No impact metrics
Proof of concept & exploit code
- github-search Search GitHub for public PoC repos
Test against your own equipment
curl -s https://vulnpedia.com/cve/CVE-2026-74597/poc.jsonMachine-readable PoC index for this CVE (for automation).Listed for defensive triage, patch verification, and authorized testing on systems you own. Machine-readable: /cve/CVE-2026-74597/poc.json
References
Technical & other
- https://git.kernel.org/stable/c/44fe898df302e91c5ee5acbc71ffa74e78e6c183
- https://git.kernel.org/stable/c/0dadb0620ab65949a8bc2439dd28ea3c942fe87d
- https://git.kernel.org/stable/c/b6816536a2990c0db44a26130a03e40b441e829b
- https://git.kernel.org/stable/c/64e41736a26f37ab6215bc2e6df125df05aceb08
- https://git.kernel.org/stable/c/484134e1eb07d700a73b1e4bbf3fb503e299be60
- https://git.kernel.org/stable/c/4eb15c465337b18f44716c499cd6ad63eee0ad54
- https://git.kernel.org/stable/c/fbf40faa0414b753212494ad197542002e66ed9e
- https://git.kernel.org/stable/c/f803c086399da277b5d0ff36a107d0f162751800