Clicking a link which is there in your email which came from an unknown source can redirect you to ____________ that automatically installs malware in your system.

A security breach occurs when a person or program gains unauthorized access to an organization's systems. This can be done by accessing a computer or network to steal local files or by bypassing network security remotely.
 

Some examples of security breaches include:
Hacking attacks
Data leaks
Insider leaks
Payment card fraud
Loss or theft of a physical hard drive of files
Human error