ActiveFax, a network-enabled fax transmission/reception system, contains a FTP server which can be used to perform FTP bounce attacks (which are useful for conducting nmap portscans in an anonymous way, among other things).
You can download this advisory from the following link: https://packetstormsecurity.com/files/download/37265/ActiveFax.txt
Source: https://packetstormsecurity.com/files/37265/ActiveFax.txt.html