Multi-Tech ProxyServer products MTPSR1-100, MTPSR1-120, MTPSR1-202ST, MTPSR2-201, and MTPSR3-200 ship with a null password, which allows remote attackers to gain administrative privileges via Telnet or HTTP.
https://exchange.xforce.ibmcloud.com/vulnerabilities/10845
http://www.securityfocus.com/bid/7203
http://www.kb.cert.org/vuls/id/495705
http://archives.neohapsis.com/archives/bugtraq/2002-12/0105.html