If the Access Control List is enforced by the Control-M/Agent and the C router is in use (default in Out-of-support Control-M/Agent versions 9.0.18 to 9.0.20 and potentially earlier unsupported versions; non-default but configurable using the JAVA_AR setting in newer versions), the verification stops at the first NULL byte encountered in the email address referenced in the client certificate. An attacker could bypass configured ACLs by using a specially crafted certificate.