An attack on the Electrum bitcoin wallet has so far netted hackers over 200 bitcoin worth around $750,000. The attack began on December 21, 2018. Though it has victimized some unsuspecting users, it can be avoided.
Electrum is a Bitcoin wallet which doesn’t require the user to download the full blockchain. Instead, servers remotely provide users with the blockchain and they access it through their wallet. It is one of the most popular Bitcoin wallet implementations and forks of it for both versions of Bitcoin Cash as well as Litecoin, Dogecoin, and Dash have been created over the years.
Malicious servers were been added to the Electrum wallet network. When users attempted a bitcoin transaction which reached one of these illegitimate servers the user received a message within the wallet application instructing them to download and install an update. The message led unsuspecting uses to the hacker’s GitHub page.