CVE-2025-15346
wolfSSL Python library `CERT_REQUIRED` mode fails to enforce client certificate requirement
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.
INFO
Published Date :
Jan. 8, 2026, 12:15 a.m.
Last Modified :
Jan. 8, 2026, 6:08 p.m.
Remotely Exploit :
Yes !
Source :
[email protected]
Affected Products
The following products are affected by CVE-2025-15346
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
| Score | Version | Severity | Vector | Exploitability Score | Impact Score | Source |
|---|---|---|---|---|---|---|
| CVSS 4.0 | CRITICAL | 50d2cd11-d01a-48ed-9441-5bfce9d63b27 | ||||
| CVSS 4.0 | CRITICAL | [email protected] |
Solution
- Update wolfssl-py to version 5.8.3 or later.
- Ensure CERT_REQUIRED is correctly configured.
- Verify mTLS configurations for strict client authentication.
- Test TLS connections with and without client certificates.
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-2025-15346.
CWE - Common Weakness Enumeration
While CVE identifies
specific instances of vulnerabilities, CWE categorizes the common flaws or
weaknesses that can lead to vulnerabilities. CVE-2025-15346 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-2025-15346
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).
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The following list is the news that have been mention
CVE-2025-15346 vulnerability anywhere in the article.
The following table lists the changes that have been made to the
CVE-2025-15346 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]
Jan. 08, 2026
Action Type Old Value New Value 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. Added CVSS V4.0 AV:N/AC:L/AT:N/PR:N/UI:N/VC:H/VI:H/VA:N/SC:N/SI:N/SA:N/E:X/CR:X/IR:X/AR:X/MAV:X/MAC:X/MAT:X/MPR:X/MUI:X/MVC:X/MVI:X/MVA:X/MSC:X/MSI:X/MSA:X/S:X/AU:Y/R:X/V:X/RE:X/U:X Added CWE CWE-287 Added CWE CWE-306 Added Reference https://github.com/wolfSSL/wolfssl-py/commit/b4517dece79f682a8f453abce5cfc0b81bae769d Added Reference https://github.com/wolfSSL/wolfssl-py/pull/62 Added Reference https://github.com/wolfSSL/wolfssl-py/releases/tag/v5.8.4-stable