CVE-2026-43091 (GCVE-0-2026-43091)
Vulnerability from cvelistv5 – Published: 2026-05-06 07:40 – Updated: 2026-08-05 12:25
VLAI
EPSS
VEX
Title
xfrm: Wait for RCU readers during policy netns exit
Summary
In the Linux kernel, the following vulnerability has been resolved:
xfrm: Wait for RCU readers during policy netns exit
xfrm_policy_fini() frees the policy_bydst hash tables after flushing the
policy work items and deleting all policies, but it does not wait for
concurrent RCU readers to leave their read-side critical sections first.
The policy_bydst tables are published via rcu_assign_pointer() and are
looked up through rcu_dereference_check(), so netns teardown must also
wait for an RCU grace period before freeing the table memory.
Fix this by adding synchronize_rcu() before freeing the policy hash tables.
Severity
7.8 (High)
Assigner
References
Impacted products
2 products
| Vendor | Product | Version | |
|---|---|---|---|
| Linux | Linux |
Affected:
e1e551bc56302b80ff930c966f9985095fb1b70d , < b66920a3348c0f63ba18365248fa21fbf0b3a937
(git)
Affected: e1e551bc56302b80ff930c966f9985095fb1b70d , < 438b1f668ad58f46ce699bb48e4698a7839e3f9e (git) Affected: e1e551bc56302b80ff930c966f9985095fb1b70d , < 3733fce2871c9bca9dd18a1a23b1432ea215a094 (git) Affected: e1e551bc56302b80ff930c966f9985095fb1b70d , < 33a3149dd81a1e2f52b80ee1e0fc380b39f3d028 (git) Affected: e1e551bc56302b80ff930c966f9985095fb1b70d , < 069daad4f2ae9c5c108131995529d5f02392c446 (git) |
|
| Linux | Linux |
Affected:
4.9
Unaffected: 0 , < 4.9 (semver) Unaffected: 6.6.136 , ≤ 6.6.* (semver) Unaffected: 6.12.83 , ≤ 6.12.* (semver) Unaffected: 6.18.24 , ≤ 6.18.* (semver) Unaffected: 6.19.14 , ≤ 6.19.* (semver) Unaffected: 7.0 , ≤ * (original_commit_for_fix) |
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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
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- 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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