CVE Alert: CVE-2025-48946

Vulnerability Summary: CVE-2025-48946

liboqs is a C-language cryptographic library that provides implementations of post-quantum cryptography algorithms. liboqs prior to version 0.13.0 supports the HQC algorithm, an algorithm with a theoretical design flaw which leads to large numbers of malformed ciphertexts sharing the same implicit rejection value. Currently, no concrete attack on the algorithm is known. However, prospective users of HQC must take extra care when using the algorithm in protocols involving key derivation. In particular, HQC does not provide the same security guarantees as Kyber or ML-KEM. There is currently no patch for the HQC flaw available in liboqs, so HQC is disabled by default in liboqs starting from version 0.13.0. OQS will update its implementation after the HQC team releases an updated algorithm specification.

Affected Endpoints:

No affected endpoints listed.

Published Date:

5/30/2025, 8:15:43 PM

❄️ CVSS Score:

Exploit Status:

Not Exploited

References:

• https://durumcrustulum.com/2024/02/24/how-to-hold-kems/#hqc
• https://github.com/open-quantum-safe/liboqs/commit/a7d698ca9c9d98990647459253183cbe29c550af
• https://github.com/open-quantum-safe/liboqs/security/advisories/GHSA-3rxw-4v8q-9gq5
• https://groups.google.com/a/list.nist.gov/g/pqc-forum/c/Wiu4ZQo3fP80

Recommended Action:

No proposed action available. Please refer to vendor documentation for updates.

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