Unauthenticated mTLS bypass via omitted verification flag
Published Jan 7, 2026 · Updated Jan 7, 2026
Improper authentication in wolfSSL-py 5.3.0 through 5.8.2 allows remote attackers to bypass mTLS by omitting a client certificate. The CERT_REQUIRED constant in wolfssl/init.py sets only WOLFSSL_VERIFY_PEER and omits WOLFSSL_VERIFY_FAIL_IF_NO_PEER_CERT, so a missing peer certificate is accepted. Exploitation requires a server that uses the affected Python wrapper for client-certificate authentication, granting access with the server's configured privileges.
Summary
What happened
Improper authentication in wolfSSL-py 5.3.0 through 5.8.2 allows remote attackers to bypass mTLS by omitting a client certificate. The CERT_REQUIRED constant in wolfssl/init.py sets only WOLFSSL_VERIFY_PEER and omits WOLFSSL_VERIFY_FAIL_IF_NO_PEER_CERT, so a missing peer certificate is accepted. Exploitation requires a server that uses the affected Python wrapper for client-certificate authentication, granting access with the server's configured privileges.
The record
- CVE
- CVE-2025-15346
- Published
- Jan 7, 2026
- Updated
- Jan 7, 2026
- Vendor
- wolfSSL
- Product
- wolfSSL-py
- Classifications
- CWE-287, CWE-306, CAPEC-220, CAPEC-115, T1190
- Attack vector
- network
- Privileges
- unauthenticated
Timeline
How it unfolded
- Jan 7, 2026CVE publishedPublication date reported by the CVE source.
- Jan 7, 2026Record updatedLatest update available in the CVE record.
Exploitability
Present is not the same as exploitable
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Is a vulnerable build present?
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- Affected versionversion=5.3.0 <=5.8.2
What conditions does exploitation require?
What is affected?
Published CVSS scores
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Attacks
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Technologies
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Your stack
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