CVE-2026-89133

wolfSSL versions 5.9.2 and earlier contain a flaw in the X.509 certificate validation logic where it fails to properly enforce NameConstraints extensions when there is an unconstrained CA tier between a name-constrained intermediate CA and the leaf certificate. wolfSSL incorrectly accepted certificates for hostnames they shouldn't be allowed to cover, due to a chain-walking state-machine bug that resets the validation state when encountering an intermediate without NameConstraints, thereby bypassing cryptographic delegation controls. This defect exists in the default build configuration that makes use of certificates where name constraint extensions are used. Thanks to Jack Lloyd, PathDiff, and Ben Smyth for reporting the issue.

CVSS v3 5.3 MEDIUM

5.3^/10

CVSS v3 : MEDIUM

Vector :

Exploitability : 3.9 / Impact : 1.4

Attack Vector NETWORK

Attack Complexity LOW

Privileges Required NONE

User Interaction NONE

Confidentiality Impact NONE

Integrity Impact LOW

Availability Impact NONE

Scope UNCHANGED

References

Link	Resource
https://github.com/wolfSSL/wolfssl/pull/10687	Issue Tracking

Configurations

Configuration 1 (hide)

cpe:2.3:a:wolfssl:wolfssl:*:*:*:*:*:*:*:*

History

02 Oct 2026, 18:58

Type	Values Removed	Values Added
CVSS	v2 : ~~unknown~~ v3 : ~~unknown~~	v2 : unknown v3 : 5.3
References	~~() https://github.com/wolfSSL/wolfssl/pull/10687 -~~	() https://github.com/wolfSSL/wolfssl/pull/10687 - Issue Tracking
First Time		Wolfssl wolfssl Wolfssl
CPE		cpe:2.3:a:wolfssl:wolfssl::::::::

27 Sep 2026, 10:16

Type	Values Removed	Values Added
New CVE

Information

Published : 2026-09-27 10:16

Updated : 2026-10-02 18:58

NVD link : CVE-2026-89133

Mitre link : CVE-2026-89133

CVE.ORG link : CVE-2026-89133

JSON object : View

Products Affected

wolfssl

wolfssl

CWE

CWE-295

Improper Certificate Validation

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