Improper Input Validation Vulnerability in Serv-U

The Serv-U web login screen accepted unsanitized characters when authenticating users through LDAP, potentially allowing attackers to bypass security checks or cause unexpected behavior. While LDAP servers typically ignore malformed input, the vulnerability could be exploited in certain configurations.

This improper input validation vulnerability (CWE-20) affects the LDAP authentication mechanism in Serv-U's web interface. An unauthenticated attacker can send specially crafted input containing insufficiently sanitized characters to the login screen; although most LDAP servers reject such input, certain configurations or downstream systems may process it unexpectedly, potentially leading to authentication bypass or injection attacks.