CVE-2026-89133

Name	CVE-2026-89133
Description	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.
Source	CVE (at NVD; CERT, ENISA, LWN, oss-sec, fulldisc, Debian ELTS, Red Hat, Ubuntu, Gentoo, SUSE bugzilla/CVE, GitHub advisories/code/issues, web search, more)
Debian Bugs	1150338

Vulnerable and fixed packages

The table below lists information on source packages.

Source Package	Release	Version	Status
wolfssl (PTS)	bookworm	5.5.4-2+deb12u2	vulnerable
	bookworm (security)	5.5.4-2+deb12u3	vulnerable
	trixie	5.7.2-0.1+deb13u2	vulnerable
	sid	5.9.2-1.2	fixed

The information below is based on the following data on fixed versions.

Package	Type	Release	Fixed Version	Urgency	Origin	Debian Bugs
wolfssl	source	(unstable)	5.9.2-1.1			1150338

Notes

[trixie] - wolfssl <no-dsa> (Minor issue)
[bookworm] - wolfssl <postponed> (Minor issue; upstream fix changes the layout of the installed struct Signer)
https://github.com/wolfSSL/wolfssl/pull/10687 (v5.9.4-stable)