Yes ofcourse. Its really possible. One of the common thing that usually happen when the virus infected your computer and goes through your wallet and takes all the details including passwords and your private keys. Many victims are experience this kind of thing. Also phishing. Phishing is when you enter your passwords into untrusted site of applications. Through this, they can easily break your security. It is know as keylogger. If you have computer with strong antivirus, you should be fine.