Firefox joins Chrome and Edge as sleeper extensions spy on users

A group of cybercriminals called DarkSpectre is believed to be behind three campaigns spread by malicious browser extensions: ShadyPanda, GhostPoster, and Zoom Stealer. We wrote about the ShadyPanda campaign in December 2025, warning users that extensions which had behaved normally for years...

DarkSpectre Browser Extension Campaigns Exposed After Impacting 8.8 Million Users Worldwide

The threat actor behind two malicious browser extension campaigns, ShadyPanda and GhostPoster, has been attributed to a third attack campaign codenamed DarkSpectre that has impacted 2.2 million users of Google Chrome, Microsoft Edge, and Mozilla Firefox. The activity is assessed to be the work of...