NetSight
critical9.8

CVE-2026-63994

In the Linux kernel, the following vulnerability has been resolved: tunnels: load network headers after skb_cow() in iptunnel_pmtud_build_icmp[v6]() Sashiko fo…

Impact

In the Linux kernel, the following vulnerability has been resolved: tunnels: load network headers after skb_cow() in iptunnel_pmtud_build_icmp[v6]() Sashiko found that iptunnel_pmtud_build_icmp() and iptunnel_pmtud_build_icmpv6() were caching ip_hdr() and ipv6_hdr() before an skb_cow() call which can reallocate skb->head. Fix this possible UAF by initializing the local variables after the skb_cow() call. Remove skb_reset_network_header() calls which were not needed.

Affected products

VendorProductAffected versions
LinuxLinux Kernel
from 5.9 before 5.10.259
from 5.11 before 5.15.210
from 5.16 before 6.1.176
from 6.2 before 6.6.143
from 6.7 before 6.12.93
from 6.13 before 6.18.35

Weakness classification

References