CVE-2026-74597
Linux kernel vulnerability
- Published22 Aug 2026
Description
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.
CVSS 3.1 breakdown
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:HRemediation
No fixed version is recorded in the NVD data. Check the vendor advisory for the latest guidance.
References
- https://git.kernel.org/stable/c/0dadb0620ab65949a8bc2439dd28ea3c942fe87d
- https://git.kernel.org/stable/c/44fe898df302e91c5ee5acbc71ffa74e78e6c183
- https://git.kernel.org/stable/c/484134e1eb07d700a73b1e4bbf3fb503e299be60
- https://git.kernel.org/stable/c/4eb15c465337b18f44716c499cd6ad63eee0ad54
- https://git.kernel.org/stable/c/64e41736a26f37ab6215bc2e6df125df05aceb08
- https://git.kernel.org/stable/c/b6816536a2990c0db44a26130a03e40b441e829b
- https://git.kernel.org/stable/c/f803c086399da277b5d0ff36a107d0f162751800
- https://git.kernel.org/stable/c/fbf40faa0414b753212494ad197542002e66ed9e
Frequently asked
Is CVE-2026-74597 being actively exploited?
CVE-2026-74597 is not in the CISA KEV catalog. Its EPSS exploit probability is 0.54%.
How severe is CVE-2026-74597?
CVE-2026-74597 has a CVSS 3.1 base score of 9.8, rated critical. EPSS estimates a 0.54% probability of exploitation.
How do I fix CVE-2026-74597?
Apply the vendor's patch or advisory guidance, then verify no affected versions remain across your devices.
How Secuno handles this
Secuno correlates vulnerabilities like CVE-2026-74597 against the real software inventory on every managed device, every day. Rather than a static severity, each match is scored in context: exploit availability, EPSS, the asset's exposure, and business criticality decide where it lands in the queue. If an affected version is present anywhere across your portfolio, it surfaces automatically with a prioritised remediation path.
Data from the NVD, CISA KEV catalog and FIRST EPSS. CVSS 3.1 base score shown where available.