liboqs: XMSS Buffer Overread Bug_CVE-2026-44518

5.3 / 10

MEDIUM

CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:L

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.

Basic Information

ID CVE-2026-44518

Source GitHub_M

Published May 29, 2026 at 18:07

Affected Product

Vendor open-quantum-safe

Product liboqs

Version < 0.16.0

Affected Versions open-quantum-safe liboqs < 0.16.0

CWE Classification

CWE-20 CWE-125

References

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    "published": "2026-05-29T18:07:07.107Z",
    "modified": "2026-05-29T18:07:07.107Z",
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