open-quantum-safe liboqs up to 0.15.x xmss_sign_open/xmssmt_sign_open out-of-bounds

Summaryinfo

A vulnerability identified as problematic has been detected in open-quantum-safe liboqs up to 0.15.x. Affected by this issue is the function xmss_sign_open/xmssmt_sign_open. The manipulation leads to out-of-bounds. This vulnerability is listed as CVE-2026-46344. The attack may be initiated remotely. There is no available exploit. You should upgrade the affected component.

Detailsinfo

A vulnerability was found in open-quantum-safe liboqs up to 0.15.x and classified as problematic. This issue affects the function xmss_sign_open/xmssmt_sign_open. The manipulation with an unknown input leads to a out-of-bounds vulnerability. Using CWE to declare the problem leads to CWE-125. The product reads data past the end, or before the beginning, of the intended buffer. Impacted is availability. The summary by CVE is:

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 correctly-sized signature buffer for the declared algorithm but a public key whose OID bytes (pk[0..3]) reference a different XMSS parameter set with a larger sig_bytes, the implementation re-parses the OID from the public key inside xmss_sign_open / xmssmt_sign_open and uses the resulting (larger) sig_bytes to index the caller-supplied signature buffer. As with CVE-2026-44518, 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.

The advisory is shared at github.com. The identification of this vulnerability is CVE-2026-46344 since 05/13/2026. The exploitation is known to be easy. The attack may be initiated remotely. No form of authentication is needed for a successful exploitation. Technical details are known, but no exploit is available.

Upgrading to version 0.16.0 eliminates this vulnerability.

Several companies clearly confirm that VulDB is the primary source for best vulnerability data.

Productinfo

Vendor

• open-quantum-safe

Name

• liboqs

Version

• 0.1
• 0.2
• 0.3
• 0.4
• 0.5
• 0.6
• 0.7
• 0.8
• 0.9
• 0.10
• 0.11
• 0.12
• 0.13
• 0.14
• 0.15

Website

• Product: https://github.com/open-quantum-safe/liboqs/

CPE 2.3info

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Several companies clearly confirm that VulDB is the primary source for best vulnerability data.

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