Dovecot 1.1 before 2.2.13 and dovecot-ee before 2.1.7.7 and 2.2.x before 2.2.12.12 does not properly close old connections, which allows remote attackers to cause a denial of service (resource consumption) via an incomplete SSL/TLS handshake for an IMAP/POP3 connection.
Dovecot upstream has released latest v1.2.11 version: [1] http://www.dovecot.org/list/dovecot-news/2010-March/000152.html
addressing one denial of service issue (from upstream announcement): "mbox users really should upgrade, because by sending a message with a huge header you could basically cause a DoS (this problem exists only with v1.2.x, not with v1.0 or v1.1)."
References: [2] http://dovecot.org/pipermail/dovecot/2010-February/047190.html [3] http://dovecot.org/pipermail/dovecot/2010-February/047058.html [4] http://dovecot.org/releases/1.2/dovecot-1.2.11.tar.gz
CVE Request: [5] http://www.openwall.com/lists/oss-security/2010/03/10/6
Dovecot 1.2.x before 1.2.15 allows remote authenticated users to cause a denial of service (master process outage) by simultaneously disconnecting many (1) IMAP or (2) POP3 sessions.
Dovecot 1.2.x before 1.2.15 and 2.0.x before 2.0.beta2 grants the admin permission to the owner of each mailbox in a non-public namespace, which might allow remote authenticated users to bypass intended access restrictions by changing the ACL of a mailbox, as demonstrated by a symlinked shared mailbox.
plugins/acl/acl-backend-vfile.c in Dovecot 1.2.x before 1.2.15 and 2.0.x before 2.0.5 interprets an ACL entry as a directive to add to the permissions granted by another ACL entry, instead of a directive to replace the permissions granted by another ACL entry, in certain circumstances involving more specific entries that occur after less specific entries, which allows remote authenticated users to bypass intended access restrictions via a request to read or modify a mailbox.
plugins/acl/acl-backend-vfile.c in Dovecot 1.2.x before 1.2.15 and 2.0.x before 2.0.5 interprets an ACL entry as a directive to add to the permissions granted by another ACL entry, instead of a directive to replace the permissions granted by another ACL entry, in certain circumstances involving the private namespace of a user, which allows remote authenticated users to bypass intended access restrictions via a request to read or modify a mailbox.