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 a single dst_cache per encap route, shared between seg6_input_core() and seg6_output_core().
Does this matter?
High impact if exploited, but EPSS currently rates exploitation as unlikely (0.44%). Schedule it in the normal patch cycle and watch for a rise in EPSS or a public exploit.
Description
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.
- CVSS 3.1
- 9.8 CRITICALCVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H
- EPSS
- 0.44% probability · 38th percentile
- Public exploits
- None in Exploit-DB
- CISA KEV
- Not listed
- Weakness
- CWE-459
- Affected
- linux/linux kernel
- Source
- 416baaa9-dc9f-4396-8d5f-8c081fb06d67
EPSS 0.4% since 26 October 2026; no change recorded yet. Points are recorded when the score first appears and whenever it moves by a percentage point or more.
References
- https://git.kernel.org/stable/c/17d87d42874f5d6c1a0ccc6d9190dfe82a9a7a6aPatch
- https://git.kernel.org/stable/c/1dec91d3b1cefb82635761b7812154af3ef46449Patch
- https://git.kernel.org/stable/c/57d0374d14fa667dec6952173b93e7e84486d5c9Patch
- https://git.kernel.org/stable/c/6305ad032b03d2ea4181b953a66e19a9a6ed053cPatch
- https://git.kernel.org/stable/c/750569d6987a0ff46317a4b86eb3907e296287bfPatch
- https://git.kernel.org/stable/c/84d458018b147176b259347103fccb7e93abd2b1Patch
- https://git.kernel.org/stable/c/c3812651b522fe8437ebb7063b75ddb95b571643Patch
- https://git.kernel.org/stable/c/fb56de5d99218de49d5d43ef3a99e062ecd0f9a1Patch
Source: NVD record, EPSS from FIRST.org, KEV from CISA, exploits from Exploit-DB. Refreshed daily. Download this record as JSON.