Vulnerability in Open-Quantum-Safe Liboqs
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.
Vulnerability class: POODLE (CVE-2014-3566)
EPSS: 0.002 (14.7th percentile) — read the EPSS interpretation.
CVSS v3 metric
CVSS v3 base score 3.7 (Low). Vector: CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:L/I:N/A:N.
Affected products
- Open-quantum-safe Liboqs — versions < 0.13.0
- Openquantumsafe Liboqs
Weakness classification (CWE)
References
- security-advisories@github.com (x_refsource_CONFIRM, Vendor Advisory)
- security-advisories@github.com (Patch, x_refsource_MISC)
- security-advisories@github.com (Product, x_refsource_MISC)
- security-advisories@github.com (Mailing List, x_refsource_MISC, Issue Tracking)
Frequently asked questions
- What is CVE-2025-48946?
- CVE-2025-48946 is a low-severity vulnerability in Open-Quantum-Safe Liboqs, classified under Use of a Broken or Risky Cryptographic Algorithm. CVSS score: 3.7/10. Published 2025-05-30.
- How severe is CVE-2025-48946?
- Low severity. CVSS v3 base score is 3.7 out of 10.