The remote host is missing an update to the system as announced in the referenced advisory.
The following package is affected: dovecot
CVE-2008-4577 The ACL plugin in Dovecot before 1.1.4 treats negative access rights as if they are positive access rights, which allows attackers to bypass intended access restrictions. CVE-2008-4578 The ACL plugin in Dovecot before 1.1.4 allows attackers to bypass intended access restrictions by using the 'k' right to create unauthorized 'parent/child/child' mailboxes.
Solution: Update your system with the appropriate patches or software upgrades.