CVE-2026-63577 Name Constraints bypass: directoryName constraint matched at any position in the DN instead of as a prefix

Improper certificate validation in the directoryName name-constraint check PkixNameConstraintValidator.WithinDNSubtree in Legion of the Bouncy Castle Inc. bc-csharp before 2.7.0 allows an attacker who controls, or can have certificates issued by, a name-constrained intermediate CA to get...

CVE-2026-63577 Name Constraints bypass: directoryName constraint matched at any position in the DN instead of as a prefix

Improper certificate validation in the directoryName name-constraint check PkixNameConstraintValidator.WithinDNSubtree in Legion of the Bouncy Castle Inc. bc-csharp before 2.7.0 allows an attacker who controls, or can have certificates issued by, a name-constrained intermediate CA to get...

CVE-2026-63577

The bc-csharp library (versions before 2.7.0 ) by Legion of the Bouncy Castle Inc. contains an improper certificate validation flaw in the PkixNameConstraintValidator.WithinDNSubtree check. The root cause is that the validator identifies the first Relative Distinguished Name (RDN) of a constraint...

CVE-2026-63577 Name Constraints bypass: directoryName constraint matched at any position in the DN instead of as a prefix

Improper certificate validation in the directoryName name-constraint check PkixNameConstraintValidator.WithinDNSubtree in Legion of the Bouncy Castle Inc. bc-csharp before 2.7.0 allows an attacker who controls, or can have certificates issued by, a name-constrained intermediate CA to get...

EUVD-2026-91228

Improper certificate validation in the directoryName name-constraint check PkixNameConstraintValidator.WithinDNSubtree in Legion of the Bouncy Castle Inc. bc-csharp before 2.7.0 allows an attacker who controls, or can have certificates issued by, a name-constrained intermediate CA to get...

PT-2026-104136

Name of the Vulnerable Software and Affected Versions bc-csharp versions prior to 2.7.0 Description Improper certificate validation occurs during the directoryName name-constraint check within the PkixNameConstraintValidator.WithinDNSubtree function. An attacker controlling a name-constrained...

CVE-2026-63577: Improper Certificate Validation

Improper certificate validation in the directoryName name-constraint check PkixNameConstraintValidator.WithinDNSubtree in Legion of the Bouncy Castle Inc. bc-csharp before 2.7.0 allows an attacker who controls, or can have certificates issued by, a name-constrained intermediate CA to get...