CVE-2026-74597
In 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.
Affected versions
Linux kernel versions
2.6.22
and later are affected. Fixed in
5.10.265,
5.15.216,
6.1.183,
6.6.152,
6.12.104,
6.18.45,
7.1.9,
7.2
and their respective stable series.
References
8 totalFrequently asked questions
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What is CVE-2026-74597?
CVE-2026-74597 is a unscored severity Linux kernel vulnerability . It affects Linux kernel versions from 2.6.22 onward and has been patched in 5.10.265, 5.15.216, 6.1.183 and others. CVE-2026-74597 has not been confirmed as actively exploited and is not listed in the CISA KEV catalog.
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Is there a patch available for CVE-2026-74597?
Yes. CVE-2026-74597 has been patched. Fixed versions include 5.10.265, 5.15.216, 6.1.183 and others. If you are running Linux kernel 2.6.22 or later up to the fix versions, apply the relevant patch for your kernel branch.
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Is CVE-2026-74597 actively exploited?
No. CVE-2026-74597 has not been confirmed as actively exploited. It is not listed in the CISA Known Exploited Vulnerabilities (KEV) catalog.