Thwarting the Wily Hacker

A windows server that a customer handles got exploited and used as an FTP repository for a few hours last week. While driving to Pennsylvania for Thanksgiving, I walked him through applying an access control list (ACL) to his router’s ethernet port to stop the abusive traffic. He’s become much more interested in how ACLs work, so today when the topic was mentioned on NANOG‘s mailing list, I forwarded this long list of network security links to him. Like most lists of links, some are more useful than others. =]