Currently the SecurityFocus staff are not aware of any vendor supplied patches for this issue. If you feel we are in error or are aware of more recent information, please mail us at: firstname.lastname@example.org.
UltraBoard 1.6 (and possibly all 1.x versions and the new beta Ultraboard 2000) are vulnerable to this Denial of Service attack.
A remote user is able to expend all of the available resources of the webserver by using a specially-devised request to the CGI. This request causes a fork, which will then consume the processor time and memory of the server.