GHSA-9cmp-wxh9-77q4CriticalCVSS 9.1

In the Linux kernel, the following vulnerability has been resolved: tunnels: do not assume...

Published
July 19, 2026
Last Modified
July 20, 2026

🔗 CVE IDs covered (1)

📋 Description

In the Linux kernel, the following vulnerability has been resolved:

tunnels: do not assume transport header in iptunnel_pmtud_check_icmp()

In some cases, iptunnel_pmtud_check_icmp() can be called while skb transport header is not set.

This triggers an out-of-bound access, because (typeof(skb->transport_header))~0U is 65535.

Access the icmp header based on IPv4 network header, after making sure icmp->type is present in skb linear part.

Note that iptunnel_pmtud_check_icmpv6()) is fine.

🔗 References (10)