A Browser Extension Risk Guide After the ShadyPanda Campaign
Dec 15, 2025
Browser Security / SaaS Security
In early December 2025, security researchers exposed a cybercrime campaign that had quietly hijacked popular Chrome and Edge browser extensions on a massive scale. A threat group dubbed ShadyPanda spent seven years playing the long game, publishing or acquiring harmless extensions, letting them run clean for years to build trust and gain millions of installs, then suddenly flipping them into malware via silent updates. In total, about 4.3 million users installed these once-legitimate add-ons, which suddenly went rogue with spyware and backdoor capabilities. This tactic was essentially a browser extension supply-chain attack. The ShadyPanda operators even earned featured and verified badges in the official Chrome Web Store and Microsoft Edge Add-ons site for some extensions, reinforcing user confidence. Because extension updates happen automatically in the background, the attackers were able to push out malicious code without users noticing a thing. Once activated in mid-2024, the...