A tiger team is commonly defined as a group of professionals who either engage in attempts to physically penetrate a secured location, or work on using hacking strategies to penetrate a virtual environment. Although this term is sometimes used more generally for any team of skilled professionals, it often has a specific meaning in IT related to cyber threats, testing and anti-hacking activities.
Techopedia explains Tiger Team
Part of the variance in the use of the term tiger team has evolved as a result of military and civilian uses. In the military, a tiger team is often a force seeking to physically infiltrate an area. In civilian use, particularly in IT, a tiger team is usually composed of skilled hackers who will seek to penetrate a network or other tech environment for the purposes of improving security and closing security loopholes.
The phenomenon of using tiger teams to address cybersecurity has raised some serious issues in terms of how to protect a network or other setup. Many times, employers have to do extensive research to determine whether skilled tiger team members could use their skills to compromise the operation in the future. Because these individuals have specific IT skills, they represent a great asset, but also a danger in terms of unauthorized access and the ability to do damage to an IT system.