Gremlin Stealer: New Stealer on Sale in Underground Forum unit42.paloaltonetworks.com/new-malwa…

Unit 42 researchers have identified new information-stealing malware written in C#, called Gremlin Stealer. This stealer’s authors have actively advertised it on a Telegram group since mid-March 2025.

This information-stealing malware exfiltrates data from its victims and uploads this information to its web server for publication. It can capture data from browsers, the clipboard and the local disk to steal sensitive data such as credit card details, browser cookies, crypto wallet information, File Transfer Protocol (FTP) and virtual private network (VPN) credentials.