Answer in brief
CVE-2026-31668 records a Critical severity (CVSS 9.8) vulnerability in seg6: separate dst_cache for input and output paths in seg6 lwtunnel. The current sources do not mark it as known exploited. The current feed maps Linux/Linux (generic), Linux/Linux (generic). Check affected ranges and fixed versions before updating.
Analysis pending evidence review
HOL Guard separates source facts from reviewed analysis. See the methodology.
CVSS is 9.8. The current sources do not mark it as known exploited. Treat this as a source-backed prioritization signal, not a statement about your environment.
Analysis status
Analysis pending evidence review
Factual feed record only; HOL analysis is not approved for indexing. Read the methodology.
The current feed maps Linux/Linux (generic), Linux/Linux (generic). Check affected ranges and fixed versions before updating.
| Package | Affected range | Fixed version |
|---|---|---|
| Linux/Linuxgeneric | 4.10 | Not reported |
| Linux/Linuxgeneric | >=6c8702c60b88651072460f3f4026c7dfe2521d12 <1dec91d3b1cefb82635761b7812154af3ef46449 || >=6c8702c60b88651072460f3f4026c7dfe2521d12 <750569d6987a0ff46317a4b86eb3907e296287bf || >=6c8702c60b88651072460f3f4026c7dfe2521d12 <57d0374d14fa667dec6952173b93e7e84486d5c9 || >=6c8702c60b88651072460f3f4026c7dfe2521d12 <84d458018b147176b259347103fccb7e93abd2b1 || >=6c8702c60b88651072460f3f4026c7dfe2521d12 <6305ad032b03d2ea4181b953a66e19a9a6ed053c || >=6c8702c60b88651072460f3f4026c7dfe2521d12 <fb56de5d99218de49d5d43ef3a99e062ecd0f9a1 || >=6c8702c60b88651072460f3f4026c7dfe2521d12 <17d87d42874f5d6c1a0ccc6d9190dfe82a9a7a6a || >=6c8702c60b88651072460f3f4026c7dfe2521d12 <c3812651b522fe8437ebb7063b75ddb95b571643 | 1dec91d3b1cefb82635761b7812154af3ef46449, 750569d6987a0ff46317a4b86eb3907e296287bf, 57d0374d14fa667dec6952173b93e7e84486d5c9, 84d458018b147176b259347103fccb7e93abd2b1, 6305ad032b03d2ea4181b953a66e19a9a6ed053c, fb56de5d99218de49d5d43ef3a99e062ecd0f9a1, 17d87d42874f5d6c1a0ccc6d9190dfe82a9a7a6a, c3812651b522fe8437ebb7063b75ddb95b571643 |
Published upstream
Apr 24, 2026
Evidence: source:cvelist:source_dates:source-dates:recordSource modified
Oct 16, 2026
Evidence: source:cvelist:source_dates:source-dates:recordFirst seen by HOL
Oct 16, 2026
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.
Quoted source text, attributed separately from HOL analysis.