Critical 9.3Published Jan 8, 2026

CVE-2025-15346A 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.

Updated under an hour ago (2026-10-19 08:20 UTC)

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Exploited in the last 30 days

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.

CVSS: 9.3 CRITICAL (v4.0, NVD)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/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
Weakness (CWE): CWE-287, CWE-306
Known exploited: Not in CISA's KEV catalog
EPSS (exploitation in the next 30 days): Not loaded for this CVE
Assigned by: Not given
NVD analysis: Deferred
Record last updated: Oct 7, 2026
First seen by InfoSec Signals: Oct 9, 2026

Affected products

No affected products are listed yet.

References

https://github.com/wolfSSL/wolfssl-py/commit/b4517dece79f682a8f453abce5cfc0b81bae769d
https://github.com/wolfSSL/wolfssl-py/pull/62
https://github.com/wolfSSL/wolfssl-py/releases/tag/v5.8.4-stable

The CVE record on cve.org NVD's entry

The CVE record is authoritative. Products marked “from the name” were identified from the CNA's free-text names, not a CPE, and are matched less certainly. This product uses the NVD API but is not endorsed or certified by the NVD.