Security breaches

A security breach is any incident that results in unauthorized access of data, applications, services, networks, and/or devices by bypassing their underlying security mechanisms.

Two such sites that hackers visit are http://zone-h.com/?zh=1 and https://haveibeenpwned.com. These websites have an archive of breached websites and their details.

For example, defacement of http://testfire.net/ was performed by an underground group named Saudi hackers. The following screenshots provides technology details: