CRITICAL: CVE-2026-31668 (CVSS 9.8) — multiple products

CVE: CVE-2026-31668

CVSS: 9.8 (3.1) — CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H

Severity: CRITICAL

Status: Critical advisory

Affected

_See vendor advisory_

Summary

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.

Verified Sources

References

https://git.kernel.org/stable/c/17d87d42874f5d6c1a0ccc6d9190dfe82a9a7a6a
https://git.kernel.org/stable/c/1dec91d3b1cefb82635761b7812154af3ef46449
https://git.kernel.org/stable/c/57d0374d14fa667dec6952173b93e7e84486d5c9
https://git.kernel.org/stable/c/6305ad032b03d2ea4181b953a66e19a9a6ed053c
https://git.kernel.org/stable/c/750569d6987a0ff46317a4b86eb3907e296287bf
https://git.kernel.org/stable/c/84d458018b147176b259347103fccb7e93abd2b1
https://git.kernel.org/stable/c/c3812651b522fe8437ebb7063b75ddb95b571643
https://git.kernel.org/stable/c/fb56de5d99218de49d5d43ef3a99e062ecd0f9a1

_Validated by the Lyrie Threat Intelligence Pipeline — 3 independent sources confirmed before publication. No speculation._

Lyrie Verdict

A vulnerability of this severity is exactly what Lyrie's anti-rogue-AI defense is built for: continuous, autonomous monitoring that doesn't wait for human reaction time.

#critical