The remote host is vulnerable to a Denial of Service (DoS) attack.
The remote host is running a version of MailEnable's IMAP service that is prone to a remote Denial of Service (DoS) attack. Specifically, an attacker requesting a nonexistent mailbox can crash the service. An attacker exploiting this flaw would need to be able to authenticate with some valid user account. Following successful authentication, the attacker would request a nonexistent mailbox. Successful exploitation leads to a loss of availability.
Upgrade to MailEnable Professional 1.7.1 or higher or to MailEnable Enterprise Edition 1.2 or higher.