8.1

CVE-2025-40158: ipv6: use RCU in ip6_output()

Deferred
AliasesUBUNTU-CVE-2025-40158DEBIAN-CVE-2025-40158
Published 12-11-2025Last modified 30-10-2026

Vulnerability summary

CVE-2025-40158 is a high (CVSS 8.1) vulnerability in linux. EPSS estimates a 0.56% chance of exploitation in the next 30 days, higher than 46.3% of scored vulnerabilities.

Priority
Prioritisesevere

Severe, CVSS 8.1 (CVE.org); no exploitation reported by the 5 checked sources; EPSS 1% (FIRST, 03-11-2026)

Source freshness unavailable

How is this decided?
CVSS score
8.1/10
010
High · v3.1 (CVE.org)
EPSS score
0.56%
0%100%
Low · +0.11 pp in 30 days
KEVNot listedNot listed by any tracked catalog.
RansomwareNot flaggedNo ransomware use recorded.
Public exploits0No public exploits recorded

Advisory lineage

Upstream 0 · Downstream 32 · Related 20
OPENSUSE-SU-2025:20172-1RHSA-2026:1690RHSA-2026:2212RHSA-2026:2264RHSA-2026:22964RHSA-2026:23237

Timeline

  1. 12-11-2025
    PublishedVulnerability first disclosed.
  2. 30-10-2026
    Last modifiedVulnerability information updated.

Description

In the Linux kernel, the following vulnerability has been resolved: ipv6: use RCU in ip6_output() Use RCU in ip6_output() in order to use dst_dev_rcu() to prevent possible UAF. We can remove rcu_read_lock()/rcu_read_unlock() pairs from ip6_finish_output2().

CVSS metrics

5 scores · 4 sources · 2 versions

EPSS trend

Probability

0.56%

Chance of exploitation in the next 30 days

Percentile

46%

Versus all other CVEs

30-day change

Increase +0.11 pp

From 0.44% on 04-10-2026

04-10-202603-11-2026

Known exploited

Compare KEV catalogs
CISA KEV

Not in the CISA KEV catalog.

ENISA CNW

Not in the ENISA CNW catalog.

CIRCL

Not in the CIRCL catalog.

Public exploits

0 found

No public exploits indexed.

Weaknesses

CWE · root cause

No weakness data has been published for this record.

Affected systems

Version check

Known conditions: network-reachable, no authentication, no user interaction (CVSS vector). Other conditions: not stated in public data.

Ubuntu155 products
  • linuxAll versions (No fix recorded) | < 6.17.0-14.14
  • linux-allwinner-5.19All versions (No fix recorded)
  • linux-awsAll versions (No fix recorded) | < 6.17.0-1007.7
  • linux-aws-5.0All versions (No fix recorded)
  • linux-aws-5.11All versions (No fix recorded)
Debian2 products
  • linuxAll versions (No fix recorded) | < 6.12.113-1 | < 6.17.6-1
  • linux-6.12< 6.12.113-1~deb12u1
Linux1 product
  • linux≥ 4a6ce2b6f2ecabbddcfe47e7cf61dd0f00b10e36, < 4549ce1057363c8dc072f40c6aa591c279eafed2 | ≥ 4a6ce2b6f2ecabbddcfe47e7cf61dd0f00b10e36, < 423895685f367b5a0a956bd14b02df0192bded4c | ≥ 4a6ce2b6f2ecabbddcfe47e7cf61dd0f00b10e36, < 92803b826e40e49a5e8a6e208f4b4574e9d19426 | ≥ 4a6ce2b6f2ecabbddcfe47e7cf61dd0f00b10e36, < 0393f85c3241c19ba8550f04a812e7d19f6b3082 | ≥ 4a6ce2b6f2ecabbddcfe47e7cf61dd0f00b10e36, < 11709573cc4e48dc34c80fc7ab9ce5b159e29695 | 4.13

3 vendors · 158 products

References

15 links
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