CVE-2025-52473: Openquantumsafe Liboqs

Medium severity, CVSS 5.5. EPSS: 0.2% chance of exploitation in the next 30 days.

liboqs is a C-language cryptographic library that provides implementations of post-quantum cryptography algorithms. Multiple secret-dependent branches have been identified in the reference implementation of the HQC key encapsulation mechanism when it is compiled with Clang for optimization levels above -O0 (-O1, -O2, etc). A proof-of-concept local attack exploits this secret-dependent information to recover the entire secret key. This vulnerability is fixed in 0.14.0.

Affected products

• Openquantumsafe Liboqs: before 0.14.0 (fixed in 0.14.0)

Published 2025-07-10. Last modified 2026-06-17.