This category spans the range of malicious software installed on a host computer for the purposes of data destruction, information gathering, creation of a backdoor, or some other nefarious activity. There are many variations currently in use, and the number expands exponentially as malware authors seek to stay at least one step ahead of the detection signatures. High-profile examples include Conficker and Zeus, but those are merely two of the more famous ones.
Incident Occurrence: 5 percent
Incident Frequency: 11.3