DHCP on Linksys BEFSR11, BEFSR41, BEFSR81, and BEFSRU31 Cable/DSL Routers, firmware version 1.45.7, does not properly clear previously used buffer contents in a BOOTP reply packet, which allows remote attackers to obtain sensitive information.
https://exchange.xforce.ibmcloud.com/vulnerabilities/16142
http://securitytracker.com/alerts/2004/May/1010288.html
http://secunia.com/advisories/11606