CVE-2026-33810
HighCVSS 8.2Exploitation Probability (EPSS)
Low risk27th percentile - higher than 27% of all known CVEs
Summary
When verifying a certificate chain with excluded DNS constraints, these constraints are not correctly applied to wildcard DNS SANs with different case. This affects only otherwise trusted chains issued by a root CA.
Risk Assessment
An attacker could exploit this to gain improper trust for certificates that should be rejected.
Recommendation
Update the software to a version that correctly handles case sensitivity in DNS constraints.
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Original NVD description (English source)
When verifying a certificate chain containing excluded DNS constraints, these constraints are not correctly applied to wildcard DNS SANs which use a different case than the constraint. This only affects validation of otherwise trusted certificate chains, issued by a root CA in the VerifyOptions.Roots CertPool, or in the system certificate pool.

