Use ThreatSTOP DNS service to protect against Malicious websites. You can use the service with your firewalls so that any sites listed in the ThreatSTOP listed sites is denied access based on your firewall rules.
About the service:
ThreatSTOP is a private, secure policy distribution network that leverages the scalability and pervasiveness of the Internet’s Domain Name Service (DNS) to reliably propagate threat information. Using standard DNS protocols, ThreatSTOP delivers:
1. “block” lists of Threat sources aggregated from the most authoritative Internet
Threat Monitors: DShield, Internet Storm Center, TQM, etc.;
2. “allow” lists such as the AOL MegaProxy; and
3. “custom allow and block lists” for secure community managment
via a private, secure, DNS system. ThreatSTOP automatically updates firewalls to control inbound and outbound connections to Threat sources, relieving you of the manual effort required to react to evolving threats in a timely manner. Additionally, unlike other services, ThreatSTOP implementation requires no special hardware or traffic re-routing and is wholly managed through a web service.
For more details and to use the service visit http://threatstop.com