Mandriva Linux Security Advisory 2010-217 - 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. Dovecot 1.2.x before 1.2.15 allows remote authenticated users to cause a denial of service by simultaneously disconnecting many POP3 sessions. Various other issues have also been addressed.
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