CVE-2026-74750

/// Technical description

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.

/// Remediation

Check the references section for vendor advisories, patches, and mitigation guidance. If immediate patching is not possible, review the CVSS vector to understand the attack surface and apply compensating controls such as network segmentation or access restrictions.

/// References