The web administration interface for Interscan VirusWall 3.6.x and earlier does not use encryption, which could allow remote attackers to obtain the administrator password to sniff the administrator password via the setpasswd.cgi program or other HTTP GET requests that contain base64 encoded usernames and passwords.
https://euvd.enisa.europa.eu/vulnerability/EUVD-2001-0133
http://www.securityfocus.com/bid/2212
http://archives.neohapsis.com/archives/bugtraq/2001-01/0235.html