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.
Metrics
Affected Vendors & Products
References
History
Thu, 08 Jan 2026 20:15:00 +0000
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ssvc
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Thu, 08 Jan 2026 10:00:00 +0000
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Wolfssl
Wolfssl wolfssl |
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| Vendors & Products |
Wolfssl
Wolfssl wolfssl |
Wed, 07 Jan 2026 23:45:00 +0000
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| 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 |
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| References |
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| Metrics |
cvssV4_0
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Status: PUBLISHED
Assigner: wolfSSL
Published:
Updated: 2026-01-08T19:22:49.043Z
Reserved: 2025-12-29T23:24:20.378Z
Link: CVE-2025-15346
Updated: 2026-01-08T19:22:46.610Z
Status : Awaiting Analysis
Published: 2026-01-08T00:15:59.393
Modified: 2026-01-08T18:08:18.457
Link: CVE-2025-15346
No data.
OpenCVE Enrichment
Updated: 2026-01-08T09:47:58Z