A security system for scanning content within a computer, including a network interface, housed within a computer, for receiving content from the Internet on its destination to an Internet application running on the computer, a database of rules corresponding to computer exploits, stored within the computer, a rule-based content scanner that communicates with said database of rules, for scanning content to recognize the presence of potential exploits therewithin, a network traffic probe, operatively coupled to the network interface and to the rule-based content scanner, for selectively diverting content from its intended destination to the rule-based content scanner, and a rule update manager that communicates with said database of rules, for updating said database of rules periodically to incorporate new rules that are made available. A method and a computer readable storage medium are also described and claimed.