Kolab stores OpenLDAP passwords in plaintext in the slapd.conf file, which may be installed world-readable, which allows local users to gain privileges.
Kolab Server 2.0.0 and 2.0.1 does not properly handle when a large email is sent with a "." in the wrong place, which causes kolabfilter to add another ".", which might break clear-text signatures and attachments. NOTE: it is not clear whether this issue crosses privilege boundaries, so this might not be a vulnerability.
Kolab Server 2.0.1, 2.0.2 and development versions pre-2.1-20051215 and earlier, when authenticating users via secure SMTP, stores authentication credentials in plaintext in the postfix.log file, which allows local users to gain privileges.