Over 40 Malicious Firefox Extensions Target Cryptocurrency Wallets, Stealing User Assets
Jul 03, 2025
Browser Security / Cryptocurrency
Cybersecurity researchers have uncovered over 40 malicious browser extensions for Mozilla Firefox that are designed to steal cryptocurrency wallet secrets, putting users' digital assets at risk. "These extensions impersonate legitimate wallet tools from widely-used platforms such as Coinbase, MetaMask, Trust Wallet, Phantom, Exodus, OKX, Keplr, MyMonero, Bitget, Leap, Ethereum Wallet, and Filfox," Koi Security researcher Yuval Ronen said . The large-scale campaign is said to have been ongoing since at least April 2025, with new extensions uploaded to the Firefox Add-ons store as recently as last week. The identified extensions have been found to artificially inflate their popularity, adding hundreds of 5-star reviews that go far beyond the total number of active installations. This strategy is employed to give them an illusion of authenticity, making it seem like they are widely adopted and tricking unsuspecting users into installing them. Another tactic adopted by ...