Bitcoin Wallet Bug Turned Fee Increases Into Theft

TLDR Electrum confirmed at least one Bitcoin theft linked to malicious servers changing pending payments. Attackers exploited the Replace-by-Fee feature to trick users into authorizing fraudulent transactions. The first report arrived on October 11, while a second user reported losing Bitcoin on October 18. Electrum released version 4.8.3 on October 24 to fix the vulnerability. Developers urged users to update their wallets and verify addresses and amounts before signing transactions. A Bitcoin wallet bug in Electrum allowed rogue servers to redirect payments when users tried to increase transaction fees.

Source: CoinCentral