CVE-2025-52473 liboqs secret-dependent branching in HQC reference implementation when compiled with Clang 17-20
A local attacker can recover secret keys from the HQC implementation in liboqs when compiled with specific Clang optimization levels, exposing cryptographic secrets.
- Exploited in the wild
- Not known
- Login needed
- Not needed
- Attackable
- Over the internet
- Victim action needed
- Not needed
- Fix
- Available
What is CVE-2025-52473?
CVE-2025-52473 is a medium-severity vulnerability in open-quantum-safe liboqs, published on 10 Jul 2025. An attacker can exploit it over the internet without logging in, with no action from the victim.
Official description
liboqs is a C-language cryptographic library that provides implementations of post-quantum cryptography algorithms. Multiple secret-dependent branches have been identified in the reference implementation of the HQC key encapsulation mechanism when it is compiled with Clang for optimization levels above -O0 (-O1, -O2, etc). A proof-of-concept local attack exploits this secret-dependent information to recover the entire secret key. This vulnerability is fixed in 0.14.0.
Weakness: CWE-200
Which versions are affected by CVE-2025-52473?
It affects 1 product.
Linux distribution packages (1)
liboqs openSUSE:Tumbleweed | All versions | 0.14.0-1.1 |
Products include Openquantumsafe Liboqs.
How do I fix CVE-2025-52473?
Upgrade to a fixed version.
Is CVE-2025-52473 being exploited?
There is no known exploitation of CVE-2025-52473 in the wild and no public exploit code.
Other vulnerabilities in open-quantum-safe liboqs
- CVE-2024-31510 Other in n/a
- CVE-2024-54137 liboqs has a correctness error in HQC decapsulation
- CVE-2024-36405 Information disclosure in liboqs
- CVE-2026-44518 liboqs: XMSS Buffer Overread Bug
- CVE-2026-46344 liboqs: Heap-buffer-overflow in XMSS verification path via OID-controlled parameter mismatch (xmss_commons.c:194)
Sources
Also known as GHSA-qq3m-rq9v-jfgm, openSUSE-SU-2025:15339-1.