Twitter user @sell9000 tweeted on April 8th, claiming to have lost $800,000 due to two Chrome extensions. Here is what happened:
Wallet extensions logged out
Keyboard logger disguised as Chrome extension
Wallet extensions logged out
@sell9000 had manually postponed the Chrome browser update multiple times, but a Windows update forced him to restart his computer and browser. After restarting and updating Chrome, he discovered that all tab histories were gone and the extensions were logged out.
This forced him to re-import mnemonic phrases for wallets like Metamask, but after importing them, his encrypted assets were gradually transferred out over a period of about three weeks, resulting in a total loss of approximately $800,000.
He emphasized that he imported the mnemonic phrases from another clean and secure computer, and the virus scan program showed no issues.
Keyboard logger disguised as
Chrome extension
During preliminary investigations, he discovered two suspicious Chrome extensions called “Sync test beta” and “Simple Game,” as well as the enabled Korean automatic translation setting in Chrome.
Among them, “Sync test beta” was confirmed to be a keyboard logger, while “Simple Game” seemed to monitor tab activities and communicate with PHP scripts from external websites.
Regarding this cybersecurity incident, user @sell9000 urged:
This is an $800,000 mistake. The lesson I learned is that if something seems off and your computer asks you to enter mnemonic phrases, then please format and reset the entire computer.
He suspects that it was an abnormal restart event of Chrome on a specific computer that led to the attack on his computer. The attacker has currently transferred the funds to exchanges MEXC and Gate.io, and it seems that no cybersecurity organization has intervened to assist.
Chrome
Google
MetaMask
Simple Game
Sync test beta
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