CVE-2025-48946

CVE-2025-48946 is a low-severity vulnerability in Openquantumsafe Liboqs with a CVSS 3.x base score of 3.7. It is not currently listed as actively exploited by CISA, and its EPSS exploit-prediction score is low. The underlying weakness is classified as CWE-327.

Key facts

Description

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.

Frequently asked questions

What is 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.
How severe is CVE-2025-48946?
CVE-2025-48946 has a CVSS 3.x base score of 3.7, rated low severity. It is exploitable over network with high attack complexity, requires no privileges and no user interaction. Impact on confidentiality is low, integrity none, and availability none.
Is CVE-2025-48946 being actively exploited?
It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 0% (10th percentile), an estimate of the probability of exploitation in the next 30 days.
What products are affected by CVE-2025-48946?
CVE-2025-48946 affects Openquantumsafe Liboqs. See the affected-products list for the exact vulnerable versions.
How do I fix CVE-2025-48946?
Review the linked vendor and NVD advisories for patched versions and mitigations, then upgrade or apply the recommended workaround.
Does CVE-2025-48946 have an EU (EUVD) identifier?
Yes. CVE-2025-48946 is tracked in the ENISA EU Vulnerability Database (EUVD) as EUVD-2025-16528.
When was CVE-2025-48946 published?
CVE-2025-48946 was published on 2025-05-30 and last updated on 2026-06-17.

References

Affected products (1)

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