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Tracker / CVE-2026-31668

CVE-2026-31668

Critical 9.8

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 and versions

linux linux_kernel
linux linux_kernel · 4.10.1 → 5.10.253
linux linux_kernel · 5.11 → 5.15.203
linux linux_kernel · 5.16 → 6.1.169
linux linux_kernel · 6.13 → 6.18.23
linux linux_kernel · 6.19 → 6.19.13
linux linux_kernel · 6.2 → 6.6.135
linux linux_kernel · 6.7 → 6.12.82

Analysis

This page is not indexable yet.Until it carries original analysis — what it actually exposes, how to check in two minutes whether a system was touched, what to do if it was — the page stays noindex. The database decides that, not the template.

References