A vulnerability in the handling of verify_mode = CERT_REQUIRED in the wolfssl Python package (wolfssl-py) causes client certificate requirements to not be fully enforced.  Because the WOLFSSL_VERIFY_FAIL_IF_NO_PEER_CERT flag was not included, the behavior effectively matched CERT_OPTIONAL: a peer certificate was verified if presented, but connections were incorrectly authenticated when no client certificate was provided.  This results in improper authentication, allowing attackers to bypass mutual TLS (mTLS) client authentication by omitting a client certificate during the TLS handshake.  The issue affects versions up to and including 5.8.2.
History

Thu, 08 Jan 2026 20:15:00 +0000

Type Values Removed Values Added
Metrics ssvc

{'options': {'Automatable': 'yes', 'Exploitation': 'none', 'Technical Impact': 'total'}, 'version': '2.0.3'}


Thu, 08 Jan 2026 10:00:00 +0000

Type Values Removed Values Added
First Time appeared Wolfssl
Wolfssl wolfssl
Vendors & Products Wolfssl
Wolfssl wolfssl

Wed, 07 Jan 2026 23:45:00 +0000

Type Values Removed Values Added
Description A vulnerability in the handling of verify_mode = CERT_REQUIRED in the wolfssl Python package (wolfssl-py) causes client certificate requirements to not be fully enforced.  Because the WOLFSSL_VERIFY_FAIL_IF_NO_PEER_CERT flag was not included, the behavior effectively matched CERT_OPTIONAL: a peer certificate was verified if presented, but connections were incorrectly authenticated when no client certificate was provided.  This results in improper authentication, allowing attackers to bypass mutual TLS (mTLS) client authentication by omitting a client certificate during the TLS handshake.  The issue affects versions up to and including 5.8.2.
Title wolfSSL Python library `CERT_REQUIRED` mode fails to enforce client certificate requirement
Weaknesses CWE-287
CWE-306
References
Metrics cvssV4_0

{'score': 9.3, 'vector': 'CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:H/VI:H/VA:N/SC:N/SI:N/SA:N/AU:Y'}


cve-icon MITRE

Status: PUBLISHED

Assigner: wolfSSL

Published:

Updated: 2026-01-08T19:22:49.043Z

Reserved: 2025-12-29T23:24:20.378Z

Link: CVE-2025-15346

cve-icon Vulnrichment

Updated: 2026-01-08T19:22:46.610Z

cve-icon NVD

Status : Awaiting Analysis

Published: 2026-01-08T00:15:59.393

Modified: 2026-01-08T18:08:18.457

Link: CVE-2025-15346

cve-icon Redhat

No data.

cve-icon OpenCVE Enrichment

Updated: 2026-01-08T09:47:58Z