Post-Quantum Cryptography Vulnerability in liboqs by Open Quantum Safe
CVE-2026-44519

5.1MEDIUM

Key Information:

Vendor

Open-quantum-safe

Status
Liboqs
Vendor
CVE Published:
6 November 2026

What is CVE-2026-44519?

The liboqs cryptographic library, prior to version 0.16.0, contains a vulnerability in the ct_select function related to the FrodoKEM suites. It lacks a value barrier in the implicit-rejection path, which can lead to distinguishable cache residency patterns. When compiled with Clang 17 or later using certain optimization levels, this flaw allows local attackers to carry out cache-timing attacks, potentially recovering private keys through repeated measurements of cache behavior. Fortunately, the issue has been addressed in version 0.16.0, which includes the necessary fixes to prevent such vulnerabilities.

Affected Version(s)

liboqs < 0.16.0

References

https://github.com/open-quantum-safe/liboqs/security/advi...
x_refsource_CONFIRM
https://github.com/open-quantum-safe/liboqs/pull/2431
x_refsource_MISC
https://github.com/open-quantum-safe/liboqs/commit/d95fc7...
x_refsource_MISC

CVSS V3.1

Score:
5.1
Severity:
MEDIUM
Confidentiality:
High
Integrity:
None
Availability:
High
Attack Vector:
Local
Attack Complexity:
High
Privileges Required:
None
User Interaction:
None
Scope:
Unchanged

Timeline

  • Vulnerability published

  • Vulnerability Reserved

.