http://confluence.atlassian.com/display/DOC/Confluence+Community+Security+Advisory+2006-01-19
Official advisory:
http://confluence.atlassian.com/display/DOC/Confluence+Security+Advisory+2006-01-20
Original report of the issue:
http://forums.atlassian.com/thread.jspa?forumID=96&threadID=9712
This issue probably affects earlier versions as well.
Original report of the issue:
http://forums.atlassian.com/thread.jspa?forumID=96&threadID=9712