In the generalized sense an attack vector is a path or means by which a hacker can gain unauthorized access to an endpoint in order to deliver a payload or to facilitate a crime. Attack vectors enable hackers to exploit vulnerabilities in the design of a network through the manipulation of applications and protocols. Attack vectors typically manipulate the software installed in the operating system of an endpoint.
Examples of attack vectors are email attachments, pop-up windows, instant messages, service configurations, new software, and firewall modifications. Human ignorance or weaknesses could also be used for engineering attack vectors. For example, users could be fooled into weakening network defenses during times of remote collaboration and file sharing.
Anti-virus software and firewalls do provide some defense or block attack vectors to some extent. Some of the mitigation measures used to thwart hackers usage of attack vectors include deep packet inspection, IP source trackers, traffic policing, VPN tunnels, network segmentation, policy-based routing, firewall layering, network-based application rules, and layer-3 switches.