The remote host is vulnerable to a flaw that allows for the bypassing of authentication.
The remote host is running the Kaspersky Anti-Spam server. This version of Anti-spam is vulnerable to a flaw where unauthenticated users can gain access to confidential data. The details of the flaw are currently unknown; however, it is believed that a successful attack would give an attacker access to confidential data.
Upgrade to version 3.0.0  or higher.