Vulnerability-Lookup

CVE-2025-40158 (GCVE-0-2025-40158)

Vulnerability from cvelistv5 – Published: 2025-11-12 10:23 – Updated: 2026-08-05 12:08

Title

ipv6: use RCU in ip6_output()

Summary

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().

Severity

8.1 (High)


                        
                          CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:H/I:H/A:H

SSVC

Exploitation: none Automatable: no Technical Impact: partial

CISA Coordinator · CISA-ADP (v2.0.3)

Decision recorded 2026-06-16 20:00 UTC

Assigner

Linux mitre root

References

2 references

URL	Tags
https://git.kernel.org/stable/c/0393f85c3241c19ba…
https://git.kernel.org/stable/c/11709573cc4e48dc3…

Impacted products

2 products

Vendor	Product	Version	CPE status
Linux	Linux	Affected: 4a6ce2b6f2ecabbddcfe47e7cf61dd0f00b10e36 , < 0393f85c3241c19ba8550f04a812e7d19f6b3082 (git) Affected: 4a6ce2b6f2ecabbddcfe47e7cf61dd0f00b10e36 , < 11709573cc4e48dc34c80fc7ab9ce5b159e29695 (git)	guessed
Linux	Linux	Affected: 4.13 Unaffected: 0 , < 4.13 (semver) Unaffected: 6.17.3 , ≤ 6.17.* (semver) Unaffected: 6.18 , ≤ * (original_commit_for_fix)	guessed

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Sightings

Author	Source	Type	Date	Other

Nomenclature

Seen: The vulnerability was mentioned, discussed, or observed by the user.
Confirmed: The vulnerability has been validated from an analyst's perspective.
Published Proof of Concept: A public proof of concept is available for this vulnerability.
Exploited: The vulnerability was observed as exploited by the user who reported the sighting.
Patched: The vulnerability was observed as successfully patched by the user who reported the sighting.
Not exploited: The vulnerability was not observed as exploited by the user who reported the sighting.
Not confirmed: The user expressed doubt about the validity of the vulnerability.
Not patched: The vulnerability was not observed as successfully patched by the user who reported the sighting.

Detection rules are retrieved from Rulezet.

The MITRE ATT&CK techniques below are AI-generated suggestions, inferred from the description of the vulnerability by the CIRCL/vulnerability-attack-technique-classification-roberta-base model, served locally by ML-Gateway. They have not been verified by an analyst and are provided for guidance only.
The approach is described in our paper Mapping CVEs to MITRE ATT&CK Techniques: A Curated Gold-Set Classifier and the Limits of LLM-Assisted Label Expansion.

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CVE-2025-40158 (GCVE-0-2025-40158)

Tags

Sightings

Nomenclature