Rit Research Labs The Bat! 1.0.11 through 2.0 creates new accounts with insecure ACLs, which allows local users to read other users' email messages.
Rit Research Labs The Bat! 1.51 for Windows allows a remote attacker to cause a denial of service by sending an email to a user's account containing a carriage return <CR> that is not followed by a line feed <LF>.