5.3
MEDIUM CVSS 3.1
CVE-2026-46344
liboqs: Heap-buffer-overflow in XMSS verification path via OID-controlled parameter mismatch (xmss_commons.c:194)
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 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.

INFO

Published Date :

May 29, 2026, 7:16 p.m.

Last Modified :

May 29, 2026, 7:16 p.m.

Remotely Exploit :

Yes !
Affected Products

The following products are affected by CVE-2026-46344 vulnerability. Even if cvefeed.io is aware of the exact versions of the products that are affected, the information is not represented in the table below.

No affected product recoded yet

CVSS Scores
The Common Vulnerability Scoring System is a standardized framework for assessing the severity of vulnerabilities in software and systems. We collect and displays CVSS scores from various sources for each CVE.
Score Version Severity Vector Exploitability Score Impact Score Source
CVSS 3.1 MEDIUM [email protected]
Solution
Update liboqs to version 0.16.0 or later to fix an out-of-bounds read vulnerability.
  • Update liboqs to version 0.16.0 or later.
  • Verify cryptographic operations using updated library.
References to Advisories, Solutions, and Tools

Here, you will find a curated list of external links that provide in-depth information, practical solutions, and valuable tools related to CVE-2026-46344.

URL Resource
https://github.com/open-quantum-safe/liboqs/commit/077e32a94f39af02209dbbc680bf8a43b774b305
https://github.com/open-quantum-safe/liboqs/security/advisories/GHSA-2wxh-55qf-c7wg
CWE - Common Weakness Enumeration

While CVE identifies specific instances of vulnerabilities, CWE categorizes the common flaws or weaknesses that can lead to vulnerabilities. CVE-2026-46344 is associated with the following CWEs:

Common Attack Pattern Enumeration and Classification (CAPEC)

Common Attack Pattern Enumeration and Classification (CAPEC) stores attack patterns, which are descriptions of the common attributes and approaches employed by adversaries to exploit the CVE-2026-46344 weaknesses.

We scan GitHub repositories to detect new proof-of-concept exploits. Following list is a collection of public exploits and proof-of-concepts, which have been published on GitHub (sorted by the most recently updated).

Results are limited to the first 15 repositories due to potential performance issues.

The following list is the news that have been mention CVE-2026-46344 vulnerability anywhere in the article.

The following table lists the changes that have been made to the CVE-2026-46344 vulnerability over time.

Vulnerability history details can be useful for understanding the evolution of a vulnerability, and for identifying the most recent changes that may impact the vulnerability's severity, exploitability, or other characteristics.

  • New CVE Received by [email protected]

    May. 29, 2026

    Action Type Old Value New Value
    Added 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 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.
    Added CVSS V3.1 AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:L
    Added CWE CWE-125
    Added Reference https://github.com/open-quantum-safe/liboqs/commit/077e32a94f39af02209dbbc680bf8a43b774b305
    Added Reference https://github.com/open-quantum-safe/liboqs/security/advisories/GHSA-2wxh-55qf-c7wg
EPSS is a daily estimate of the probability of exploitation activity being observed over the next 30 days. Following chart shows the EPSS score history of the vulnerability.