CVE-2026-5263 URI nameConstraints not enforced in ConfirmNameConstraints()
A malicious sub-CA can issue leaf certificates with invalid URI SANs that wolfSSL accepts, bypassing nameConstraints validation.
- Exploited in the wild
- Not known
- Login needed
- An administrator
- Attackable
- Over the internet
- Victim action needed
- Not needed
- Fix
- Available
What is CVE-2026-5263?
CVE-2026-5263 is a high-severity vulnerability in Wolfssl Wolfssl, published on 9 Apr 2026. An attacker needs administrator access to exploit it, with no action from the victim.
Official description
URI nameConstraints from constrained intermediate CAs are parsed but not enforced during certificate chain verification in wolfcrypt/src/asn.c. A compromised or malicious sub-CA could issue leaf certificates with URI SAN entries that violate the nameConstraints of the issuing CA, and wolfSSL would accept them as valid.
Weakness: CWE-295
Which versions are affected by CVE-2026-5263?
It affects 1 product.
Products include Wolfssl Wolfssl.
How do I fix CVE-2026-5263?
Apply the vendor's patch.
Is CVE-2026-5263 being exploited?
There is no known exploitation of CVE-2026-5263 in the wild and no public exploit code.
Other vulnerabilities in Wolfssl Wolfssl
Sources
Also known as DEBIAN-CVE-2026-5263, GHSA-9xmr-c663-3rpr, JLSEC-2026-717, UBUNTU-CVE-2026-5263.