A black hat hacker is a computer criminal, who exploits security vulnerabilities in computer systems to gain unauthorized access to data and systems. Black hat hackers are typically motivated by financial gain, although some may also do it for malicious intent, such as disrupting a system for political reasons. Black hat hackers employ a wide range of techniques, including social engineering, brute-force attacks, and malicious software, to achieve their goals. They are also known to use zero-day exploits, which exploit vulnerabilities that have not yet been identified and patched by the affected system’s vendor.

A black hat hacker typically has advanced knowledge of computer networks and the ability to write custom code to exploit security flaws. They are also well-versed in methods of obfuscating their activities, often using encryption and proxy servers to hide their tracks. Black hat hackers have been responsible for some of the most destructive cyber attacks in history, such as the Equifax data breach and the WannaCry ransomware attack.

In contrast to black hat hackers, there are white hat hackers, who use their knowledge and skills to help organizations strengthen their security. White hat hackers are hired by organizations to find and exploit security vulnerabilities, and then help them patch them before they can be exploited by malicious actors.