CVE-2026-89134
Critical
Description
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.
SeverityCritical
CVSS9.1
Exploit probability—
ProductWolfssl
PublishedSep 27, 2026
First seenSep 27, 2026
Weakness typeCWE-295CWE-295
How to fix
Sources list no fixed version or patch link for this vulnerability.
Affected products
| Product | Affected versions | Fixed in |
|---|---|---|
| wolfssl wolfssl | 5.9.2 | — |
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