CVE-2026-89134

A certificate with no dNSName SAN but another SAN type present (e.g. registeredID or iPAddress) bypassed the Subject CN dNSName name-constraint check. The CN-as-DNS fallback was gated on cert->subjectCN != NULL && cert->altNames == NULL && !cert->isCA instead of "no dNSName SAN", so an out-of-scope CN was accepted. This incomplete fix from CVE-2026-6731, leading to the name-constraint check issue, was introduced in wolfSSL version 5.9.2.

CVSS v3 9.1 CRITICAL

9.1^/10

CVSS v3 : CRITICAL

Vector :

Exploitability : 3.9 / Impact : 5.2

Attack Vector NETWORK

Attack Complexity LOW

Privileges Required NONE

User Interaction NONE

Confidentiality Impact NONE

Integrity Impact HIGH

Availability Impact HIGH

Scope UNCHANGED

References

Link	Resource
https://github.com/wolfSSL/wolfssl/pull/10837	Patch

Configurations

Configuration 1 (hide)

cpe:2.3:a:wolfssl:wolfssl:5.9.2:*:*:*:*:*:*:*

History

02 Oct 2026, 18:57

Type	Values Removed	Values Added
References	~~() https://github.com/wolfSSL/wolfssl/pull/10837 -~~	() https://github.com/wolfSSL/wolfssl/pull/10837 - Patch
CPE		cpe:2.3:a:wolfssl:wolfssl:5.9.2:::::::*
CVSS	v2 : ~~unknown~~ v3 : ~~unknown~~	v2 : unknown v3 : 9.1
First Time		Wolfssl 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 18:57

NVD link : CVE-2026-89134

Mitre link : CVE-2026-89134

CVE.ORG link : CVE-2026-89134

JSON object : View

Products Affected

wolfssl

wolfssl

CWE

CWE-295

Improper Certificate Validation

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