CVE-2026-48057
Severity CVSS v4.0:
LOW
Type:
CWE-295
Improper Certificate Validation
Publication date:
06/11/2026
Last modified:
06/11/2026
Description
Botan is a C++ cryptography library. Prior to 3.13.0, Botan's X.509 Distinguished Name decoder flattens the Attribute-Value Assertions in each Relative Distinguished Name and loses multi-value RDN grouping before DN name-constraint enforcement. An attacker controlling a name-constrained intermediate CA can issue a certificate with a multi-value RDN whose first Common Name matches the permitted constraint and whose second Common Name is attacker-chosen, causing the constraint check to accept the flattened first value. If the certificate contains no subjectAlternativeName extension, the second Common Name can then be accepted as a hostname; Botan does not fall back to Common Name hostname matching when any subjectAlternativeName is present. The exposure is limited to deployments using DN name constraints, which are uncommon outside internal PKIs, and to certificates without a subjectAlternativeName. This issue is fixed in version 3.13.0.
Impact
Base Score 4.0
2.10
Severity 4.0
LOW


