9.8

CVE-2026-31668: linux

CVSS: 9.8v3.1CriticalAnalyzed
AliasesUBUNTU-CVE-2026-31668DEBIAN-CVE-2026-31668
Published 24-04-2026Last modified 16-10-2026
Open JSON

Vulnerability summary

CVE-2026-31668 is a critical (CVSS 9.8) vulnerability in linux. EPSS estimates a 0.44% chance of exploitation in the next 30 days, higher than 37.1% of scored vulnerabilities.

Overall risk
70/100
0100
High · default modelHow is this calculated?
CVSS score
9.8/10
010
Critical · v3.1 (CVE.org)
EPSS score
0.44%
0%100%
Low · 0.00 pp in 30 days
KEVNot listedIn no KEV catalog
RansomwareNone recordedNo known use recorded
Public exploits0No public exploits recorded

Advisory lineage

Upstream 0 · Downstream 30 · Related 39
MGASA-2026-0108MGASA-2026-0110SUSE-SU-2026:21834-1SUSE-SU-2026:2238-1SUSE-SU-2026:2450-1USN-8492-1

Timeline

  1. 24-04-2026
    PublishedVulnerability first disclosed.
  2. 16-10-2026
    Last modifiedVulnerability information updated.

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 metrics

5 scores · 4 sources · 2 versions

EPSS trend

Probability

0.44%

Chance of exploitation in the next 30 days

Percentile

37%

Versus all other CVEs

30-day change

0.00 pp

From 0.44% on 19-09-2026

19-09-202619-10-2026
EPSS score
0.44%

Known exploited

Compare KEV catalogs

Not in any of the 3 tracked catalogs.

Public exploits

0 found

No public exploits indexed.

Weaknesses

CWE · root cause

No weakness data has been published for this record.

Affected systems

Ubuntu156 products
  • linux< 4.15.0-254.266 | < 5.4.0-234.254 | < 5.15.0-185.195 | < 6.8.0-134.134 | < 6.17.0-40.40
  • linux-allwinner-5.19All versions (No fix recorded)
  • linux-aws< 4.15.0-1195.208 | < 5.4.0-1162.173 | < 5.15.0-1111.118 | < 6.8.0-1060.63 | < 6.17.0-1019.19
  • linux-aws-5.0All versions (No fix recorded)
  • linux-aws-5.11All versions (No fix recorded)
Linux2 products
  • linux≥ 6c8702c60b88651072460f3f4026c7dfe2521d12, < 1dec91d3b1cefb82635761b7812154af3ef46449 | ≥ 6c8702c60b88651072460f3f4026c7dfe2521d12, < 750569d6987a0ff46317a4b86eb3907e296287bf | ≥ 6c8702c60b88651072460f3f4026c7dfe2521d12, < 57d0374d14fa667dec6952173b93e7e84486d5c9 | ≥ 6c8702c60b88651072460f3f4026c7dfe2521d12, < 84d458018b147176b259347103fccb7e93abd2b1 | ≥ 6c8702c60b88651072460f3f4026c7dfe2521d12, < 6305ad032b03d2ea4181b953a66e19a9a6ed053c | ≥ 6c8702c60b88651072460f3f4026c7dfe2521d12, < fb56de5d99218de49d5d43ef3a99e062ecd0f9a1 | ≥ 6c8702c60b88651072460f3f4026c7dfe2521d12, < 17d87d42874f5d6c1a0ccc6d9190dfe82a9a7a6a | ≥ 6c8702c60b88651072460f3f4026c7dfe2521d12, < c3812651b522fe8437ebb7063b75ddb95b571643 | 4.10
  • linux_kernel≥ 4.10.1, < 5.10.253 | ≥ 5.11, < 5.15.203 | ≥ 5.16, < 6.1.169 | ≥ 6.2, < 6.6.135 | ≥ 6.7, < 6.12.82 | ≥ 6.13, < 6.18.23 | ≥ 6.19, < 6.19.13 | 4.10 | 7.0:rc1 | 7.0:rc2 | 7.0:rc3 | 7.0:rc4 | 7.0:rc5 | 7.0:rc6 | 7.0:rc7
Debian1 product
  • linux< 6.1.170-1 | < 6.12.85-1 | < 6.19.13-1

3 vendors · 159 products

References

49 links
Show all 49 references