CVE-2026-74750

In the Linux kernel, the following vulnerability has been resolved: ovpn: defer key slot crypto freeing to workqueue Key slots are released through a kref and the existing release path frees the AEAD transforms from an RCU callback. That is not safe for all crypto implementations: crypto_free_aead can sleep, for example when an async or hardware implementation has teardown work to complete. Use queue_rcu_work for key-slot release. This keeps the RCU grace period needed by lockless key-slot readers, but runs the actual crypto teardown from workqueue context where sleeping is allowed. Once the rcu_work callback runs, pre-existing RCU readers are gone, and the final kref put already proves that no transform user remains, so the worker can release the AEAD transforms and free the slot directly. The previous patch drains ovpn_wq during module exit, so queued key-slot teardown work cannot outlive module text.

CVSS v3 7.5 HIGH

7.5^/10

CVSS v3 : HIGH

Vector :

Exploitability : 3.9 / Impact : 3.6

Attack Vector NETWORK

Attack Complexity LOW

Privileges Required NONE

User Interaction NONE

Confidentiality Impact NONE

Integrity Impact NONE

Availability Impact HIGH

Scope UNCHANGED

References

Link	Resource
https://git.kernel.org/stable/c/0f77ed5ee91946ea63e29f2e0ff9dc9e722d8da3
https://git.kernel.org/stable/c/2da3dfa1ddfe55a065f484750c83660e3bd4ac00

Configurations

No configuration.

History

No history.

Information

Published : 2026-08-26 15:16

Updated : 2026-08-27 06:17

NVD link : CVE-2026-74750

Mitre link : CVE-2026-74750

CVE.ORG link : CVE-2026-74750

JSON object : View

Products Affected

No product.

CWE

No CWE.

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