Blended threats are sophisticated attacks that bundle some of the worst aspects of Viruses, Worms, Trojan Horses and Malware into one single threat. Blended threats can use server and Internet vulnerabilities to initiate, then transmit and spread an attack. Characteristics of blended threats are that they cause harm to the infected system or network, they propagate using multiple methods, the attack can come from multiple points, and blended threats exploit vulnerabilities. To be considered a blended thread, the attack would normally transport multiple attacks in one payload. For example it wouldn't just launch a DoS attack — it could also install a Backdoor and maybe damage a local system in one shot. Additionally, blended threats are designed to use multiple modes of transport. So, while worms travel and spread through e-mail, a single blended threat could use multiple routes including e-mail, IRC and P2P. Lastly, rather than a specific attack on predetermined .exe files, a blended thread could do multiple malicious acts, like modify your executables, HTML files and registry keys at the same time — basically it can cause damage within several areas of your network at one time.