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.

Directory traversal vulnerability in the ManageSieve implementation in Dovecot 1.0.15, 1.1, and 1.2 allows remote attackers to read and modify arbitrary .sieve files via a ".." (dot dot) in a script name.

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.

Dovecot before 1.0.11, when configured to use mailextragroups to allow Dovecot to create dotlocks in /var/mail, might allow local users to read sensitive mail files for other users, or modify files or directories that are writable by group, via a symlink attack.