CVE-2025-40158 (GCVE-0-2025-40158)
Vulnerability from cvelistv5 – Published: 2025-11-12 10:23 – Updated: 2026-08-05 12:08
VLAI
EPSS
VEX
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)
SSVC
Exploitation: none
Automatable: no
Technical Impact: partial
CISA Coordinator · CISA-ADP (v2.0.3)
Decision recorded 2026-06-16 20:00 UTC
Assigner
References
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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Experimental. This forecast is provided for visualization only and may change without notice. Do not use it for operational decisions.
Forecast uses a logistic model when the trend is rising, or an exponential decay model when the trend is falling. Fitted via linearized least squares.
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.
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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.
Browse all ATT&CK techniques and the vulnerabilities related to each.
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.
Browse all ATT&CK techniques and the vulnerabilities related to each.
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Related by attack behaviour
Vulnerabilities whose description is nearest to this one in the vector space of the CIRCL/vulnerability-attack-technique-biencoder model. This is a similarity search over the bi-encoder space (plain cosine), not a classification, and it has no measured accuracy.
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