liboqs is a C-language cryptographic library that provides implementations of post-quantum cryptography algorithms. A correctness error has been identified in the reference implementation of the HQC key encapsulation mechanism. Due to an indexing error, part of the secret key is incorrectly treated as non-secret data. This results in an incorrect shared secret value being returned when the decapsulation function is called with a malformed ciphertext. This vulnerability is fixed in 0.12.0.

oqs-provider is a provider for the OpenSSL 3 cryptography library that adds support for post-quantum cryptography in TLS, X.509, and S/MIME using post-quantum algorithms from liboqs. Flaws have been identified in the way oqs-provider handles lengths decoded with DECODE_UINT32 at the start of serialized hybrid (traditional + post-quantum) keys and signatures. Unchecked length values are later used for memory reads and writes; malformed input can lead to crashes or information leakage. Handling of plain/non-hybrid PQ key operation is not affected. This issue has been patched in in v0.6.1. All users are advised to upgrade. There are no workarounds for this issue.

liboqs is a C-language cryptographic library that provides implementations of post-quantum cryptography algorithms. A control-flow timing lean has been identified in the reference implementation of the Kyber key encapsulation mechanism when it is compiled with Clang 15-18 for `-Os`, `-O1`, and other compilation options. A proof-of-concept local attack on the reference implementation leaks the entire ML-KEM 512 secret key in ~10 minutes using end-to-end decapsulation timing measurements. The issue has been fixed in version 0.10.1. As a possible workaround, some compiler options may produce vectorized code that does not leak secret information, however relying on these compiler options as a workaround may not be reliable.