Executive brief
A vulnerability was identified in the Linux kernel's parallel crypto wrapper (pcrypt) that could lead to system instability or incorrect processing of encrypted data. The issue stems from how the system handles high-volume cryptographic requests when the processing queue is full. If exploited, this could potentially impact the reliability of secure communications or data protection services on the affected system.
Technical details
A vulnerability in the Linux kernel crypto subsystem's pcrypt (parallel crypto) module was discovered where MAY_BACKLOG requests were not correctly handled. Specifically, the pcrypt_aead_enc and pcrypt_aead_dec functions failed to account for the -EBUSY return code, which indicates a request has been backlogged. Additionally, the pcrypt_aead_done callback did not properly filter out -EINPROGRESS notifications. This logic error can cause the padata infrastructure to proceed with serializing requests prematurely or incorrectly. The fix involves updating the return code checks to include -EBUSY and ensuring -EINPROGRESS notifications are ignored in the completion handler.
Affected products
- Linux Linux Kernel Fixed in 4627189, 77d55bc, 915b692, 9f1cbca, eb34e24
Timeline
- 2026-04-16: patched: Initial patch authored by Herbert Xu
- 2026-05-19: disclosed: CVE published to NVD
References
- https://git.kernel.org/stable/c/46271895ddfb1ba41f89f7e0dffbe9c2bcf7380a
- https://git.kernel.org/stable/c/77d55bc8675ee851ed639dc9be77325a8024cf67
- https://git.kernel.org/stable/c/915b692e6cb723aac658c25eb82c58fd81235110
- https://git.kernel.org/stable/c/9f1cbca178c03188e201ed175251372149bb25f2
- https://git.kernel.org/stable/c/eb34e243df57e32f4c08fa191f3602ea19076276