NetSight
critical9.8

CVE-2026-31668

In the Linux kernel, the following vulnerability has been resolved: seg6: separate dst_cache for input and output paths in seg6 lwtunnel The seg6 lwtunnel uses…

Impact

In the Linux kernel, the following vulnerability has been resolved: seg6: separate dst_cache for input and output paths in seg6 lwtunnel The seg6 lwtunnel uses a single dst_cache per encap route, shared between seg6_input_core() and seg6_output_core(). These two paths can perform the post-encap SID lookup in different routing contexts (e.g., ip rules matching on the ingress interface, or VRF table separation). Whichever path runs first populates the cache, and the other reuses it blindly, bypassing its own lookup. Fix this by splitting the cache into cache_input and cache_output, so each path maintains its own cached dst independently.

Affected products

VendorProductAffected versions
LinuxLinux Kernel
from 4.10.1 before 5.10.253
from 5.11 before 5.15.203
from 5.16 before 6.1.169
from 6.2 before 6.6.135
from 6.7 before 6.12.82
from 6.13 before 6.18.23

Weakness classification

References