Mantis 1.0.0rc3 does not properly handle "Make note private" when a bug is being resolved, which has unknown impact and attack vectors, probably related to an information leak.
https://euvd.enisa.europa.eu/vulnerability/EUVD-2005-4519
http://www.vupen.com/english/advisories/2005/3064
http://www.trapkit.de/advisories/TKADV2005-11-002.txt
http://www.debian.org/security/2005/dsa-944
http://sourceforge.net/project/shownotes.php?release_id=377934&group_id=14963