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.
Affected products
linux: linux kernel
References8
- git.kernel.org/stable/c/17d87d42874f5d6c1a0ccc6d9190dfe82a9a7a6a Patch
- git.kernel.org/stable/c/1dec91d3b1cefb82635761b7812154af3ef46449 Patch
- git.kernel.org/stable/c/57d0374d14fa667dec6952173b93e7e84486d5c9 Patch
- git.kernel.org/stable/c/6305ad032b03d2ea4181b953a66e19a9a6ed053c Patch
- git.kernel.org/stable/c/750569d6987a0ff46317a4b86eb3907e296287bf Patch
- git.kernel.org/stable/c/84d458018b147176b259347103fccb7e93abd2b1 Patch
- git.kernel.org/stable/c/c3812651b522fe8437ebb7063b75ddb95b571643 Patch
- git.kernel.org/stable/c/fb56de5d99218de49d5d43ef3a99e062ecd0f9a1 Patch
Metrics
- CVSS 3.1
-
9.8
CRITICAL
Score source: CNA
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H - EPSS — exploit probability
- 0% percentile: 39 · as of 13 November 2026
- CWE
- CWE-459
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