CVE-2026-89133 (GCVE-0-2026-89133)

Vulnerability from cvelistv5 – Published: 2026-09-27 09:18 – Updated: 2026-09-27 09:18
VLAI
Title
NameConstraints not enforced across unconstrained intermediate CA
Summary
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.
Severity
6.3 (Medium)
CVSS:4.0/AV:N/AC:H/AT:N/PR:N/UI:N/VC:L/VI:L/VA:N/SC:N/SI:N/SA:N
CWE
  • CWE-295 - Improper Certificate Validation
Assigner
References
Impacted products
Vendor Product Version CPE status
wolfSSL wolfSSL Affected: 0 , ≤ 5.9.2 (semver)
guessed Create a notification for this product.
Date Public
2026-09-26 12:00
Credits
Jack Lloyd PathDiff Ben Smyth
Show details on NVD website
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