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.

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)

Published 2025-05-30 · last modified 2026-06-17.

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.

EPSS exploit prediction

EPSS: 0.002 (13.9th percentile), scored 2026-10-20.

Very low probability of exploitation in the next 30 days; routine patching cadence is appropriate. 14th percentile — 13.9% of CVEs in the catalogue have a lower EPSS than this one. How to read EPSS.

EPSS over last 30 days · oldest: 0.002 · newest: 0.002 · change: 0.000

Affected products

Open-Quantum-Safe Liboqs — versions < 0.13.0
Openquantumsafe Liboqs

Weakness classification (CWE)

CWE-327 — Use of a Broken or Risky Cryptographic Algorithm

References

github.com/open-quantum-safe/liboqs/security/advisories/GHSA-3rxw-4v8q-9gq5 (Vendor Advisory)
github.com/open-quantum-safe/liboqs/commit/a7d698ca9c9d98990647459253183cbe29c5… (Patch)
durumcrustulum.com/2024/02/24/how-to-hold-kems/ (Product)
groups.google.com/a/list.nist.gov/g/pqc-forum/c/Wiu4ZQo3fP80 (Mailing List, 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.