Remote Access Trojans (RATs) are malicious software programs that enable criminals to control your computer through your Internet connection. A RAT can let a criminal view and change your computer's files and functions, monitor and record your activities, and use your computer to attack other computers. Additionally, RATs allow criminals to do these things without your knowledge.

RATs often come hidden in illicit software and other files and programs that you might download from the Internet. They can also appear in e-mail or instant messages disguised as attachments such as funny images, greeting cards, or audio and video files. If you click the attachments to open them, a RAT might be secretly downloaded as well. Sometimes a RAT can even get on your computer without any action from you, by taking advantage of vulnerabilities in software or the Internet.
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