Trend Micro InterScan AppletTrap 2.0 does not properly filter URLs when they are modified in certain ways such as (1) using a double slash (//) instead of a single slash, (2) URL-encoded characters, (3) requesting the IP address instead of the domain name, or (4) using a leading 0 in an octet of an IP address.
https://exchange.xforce.ibmcloud.com/vulnerabilities/6819
https://exchange.xforce.ibmcloud.com/vulnerabilities/6818
https://exchange.xforce.ibmcloud.com/vulnerabilities/6817
https://exchange.xforce.ibmcloud.com/vulnerabilities/6816
http://www.securityfocus.com/bid/3000
http://www.securityfocus.com/bid/2998
http://www.securityfocus.com/bid/2996
http://archives.neohapsis.com/archives/bugtraq/2001-07/0129.html