xfrm: Wait for RCU readers during policy netns exit
Summary
| CVE | CVE-2026-43091 |
|---|---|
| State | PUBLISHED |
| Assigner | Linux |
| Source Priority | CVE Program / NVD first with legacy fallback |
| Published | 2026-05-06 10:16:22 UTC |
| Updated | 2026-05-08 13:16:38 UTC |
| Description | 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. |
Risk And Classification
Primary CVSS: v3.1 7.8 HIGH from 416baaa9-dc9f-4396-8d5f-8c081fb06d67
CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H
EPSS: 0.000130000 probability, percentile 0.023990000 (date 2026-05-12)
| Version | Source | Type | Score | Severity | Vector |
|---|---|---|---|---|---|
| 3.1 | 416baaa9-dc9f-4396-8d5f-8c081fb06d67 | Secondary | 7.8 | HIGH | CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H |
| 3.1 | CNA | DECLARED | 7.8 | HIGH | CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H |
CVSS v3.1 Breakdown
Attack Vector
LocalAttack Complexity
LowPrivileges Required
LowUser Interaction
NoneScope
UnchangedConfidentiality
HighIntegrity
HighAvailability
HighCVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H
Vendor Declared Affected Products
| Source | Vendor | Product | Version | Platforms |
|---|---|---|---|---|
| CNA | Linux | Linux | affected e1e551bc56302b80ff930c966f9985095fb1b70d b66920a3348c0f63ba18365248fa21fbf0b3a937 git | Not specified |
| CNA | Linux | Linux | affected e1e551bc56302b80ff930c966f9985095fb1b70d 438b1f668ad58f46ce699bb48e4698a7839e3f9e git | Not specified |
| CNA | Linux | Linux | affected e1e551bc56302b80ff930c966f9985095fb1b70d 3733fce2871c9bca9dd18a1a23b1432ea215a094 git | Not specified |
| CNA | Linux | Linux | affected e1e551bc56302b80ff930c966f9985095fb1b70d 33a3149dd81a1e2f52b80ee1e0fc380b39f3d028 git | Not specified |
| CNA | Linux | Linux | affected e1e551bc56302b80ff930c966f9985095fb1b70d 069daad4f2ae9c5c108131995529d5f02392c446 git | Not specified |
| CNA | Linux | Linux | affected 4.9 | Not specified |
| CNA | Linux | Linux | unaffected 4.9 semver | Not specified |
| CNA | Linux | Linux | unaffected 6.6.136 6.6.* semver | Not specified |
| CNA | Linux | Linux | unaffected 6.12.83 6.12.* semver | Not specified |
| CNA | Linux | Linux | unaffected 6.18.24 6.18.* semver | Not specified |
| CNA | Linux | Linux | unaffected 6.19.14 6.19.* semver | Not specified |
| CNA | Linux | Linux | unaffected 7.0 * original_commit_for_fix | Not specified |
References
| Reference | Source | Link | Tags |
|---|---|---|---|
| git.kernel.org/stable/c/3733fce2871c9bca9dd18a1a23b1432ea215a094 | 416baaa9-dc9f-4396-8d5f-8c081fb06d67 | git.kernel.org | |
| git.kernel.org/stable/c/33a3149dd81a1e2f52b80ee1e0fc380b39f3d028 | 416baaa9-dc9f-4396-8d5f-8c081fb06d67 | git.kernel.org | |
| git.kernel.org/stable/c/b66920a3348c0f63ba18365248fa21fbf0b3a937 | 416baaa9-dc9f-4396-8d5f-8c081fb06d67 | git.kernel.org | |
| git.kernel.org/stable/c/069daad4f2ae9c5c108131995529d5f02392c446 | 416baaa9-dc9f-4396-8d5f-8c081fb06d67 | git.kernel.org | |
| git.kernel.org/stable/c/438b1f668ad58f46ce699bb48e4698a7839e3f9e | 416baaa9-dc9f-4396-8d5f-8c081fb06d67 | git.kernel.org | |
| CVE Program record | CVE.ORG | www.cve.org | canonical |
| NVD vulnerability detail | NVD | nvd.nist.gov | canonical, analysis |
No vendor comments have been submitted for this CVE.
There are currently no legacy QID mappings associated with this CVE.