Vigil@nce - Dovecot: incorrect processing of ACLs
October 2010 by Vigil@nce
This bulletin was written by Vigil@nce : http://vigilance.fr/
SYNTHESIS OF THE VULNERABILITY
In some cases, ACLs defined by the administrator are not honored by Dovecot.
Creation date: 05/10/2010
DESCRIPTION OF THE VULNERABILITY
The Dovecot program is an IMAP/POP3 server. Its ACL plugin can be used to define access restrictions.
When an object has several ACLs, they have to be applied in the order from the most general to the most specific. However, they are simply merged. So, for example, when the ACL on the mailbox of an user is more restrictive than the general ACL, it is not applied.
In some cases, ACLs defined by the administrator are therefore not honored by Dovecot.
ACCESS TO THE COMPLETE VIGIL@NCE BULLETIN