Blended threats combine the characteristics of viruses, worms, Trojan Horses, and malicious code with server and Internet vulnerabilities to initiate, transmit, and spread an attack. By using multiple methods and techniques, blended threats can rapidly spread and cause widespread damage. Characteristics of blended threats include: causes harm, propagates by multiple methods, attacks from multiple points, and exploits vulnerabilities. [Source: Symantec Security Response Web site
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