CVE-2026-44518 liboqs: XMSS Buffer Overread Bug
- Exploited in the wild
- Not known
- Fix
- Available
What is CVE-2026-44518?
CVE-2026-44518 is a medium-severity vulnerability in open-quantum-safe liboqs, published on 29 May 2026.
Official description
liboqs is a C-language cryptographic library that provides implementations of post-quantum cryptography algorithms. Prior to 0.16.0, an out-of-bounds read has been identified in the XMSS and XMSS^MT stateful signature verification code. When the verification function is called with a signature buffer shorter than the expected signature size for the given parameter set, the implementation does not validate the caller-supplied length and proceeds to read past the end of the buffer. The out-of-bounds bytes are consumed only as input to an internal hash computation and are not returned to the caller, so no oracle exists to leak their contents to an attacker. The primary observable effect is a possible crash (denial of service) of the verifying process if the read crosses into an unmapped memory page. This vulnerability is fixed in 0.16.0.
Which versions are affected by CVE-2026-44518?
It affects 1 product.
Products include Openquantumsafe Liboqs.
How do I fix CVE-2026-44518?
Upgrade to a fixed version.
Is CVE-2026-44518 being exploited?
There is no known exploitation of CVE-2026-44518 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-2025-52473 liboqs secret-dependent branching in HQC reference implementation when compiled with Clang 17-20
- CVE-2024-36405 Information disclosure in liboqs
- 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-wf7v-fhxj-73m2.