CVE-2026-43091 (GCVE-0-2026-43091)

Vulnerability from cvelistv5 – Published: 2026-05-06 07:40 – Updated: 2026-05-11 22:17
VLAI?
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)
CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H
Assigner
References
Impacted 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)
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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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  }
}


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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

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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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