Pegasus is a highly sophisticated and controversial spyware tool developed by the Israeli cybersecurity firm NSO Group. Pegasus is designed to infiltrate and infect mobile devices, including smartphones, and it allows the attacker to remotely monitor and collect a wide range of information from the compromised device. This information can include text messages, call logs, emails, GPS location data, and more. It can also be used to activate the device's microphone and camera for audio and video surveillance.