Electrum Wallet has patched a high-severity vulnerability that allowed hackers to redirect Bitcoin payments when users attempted to increase transaction fees, enabling funds to be stolen without private keys.

The vulnerability affected Electrum versions prior to 4.8.3, exploiting the wallet's reliance on external servers to track unconfirmed transactions. Malicious servers could manipulate payment information displayed to users before they authorized additional fees. Developers disclosed the vulnerability on October 24 and confirmed that malicious servers had exploited the weakness, resulting in at least one user losing Bitcoin. Electrum has released version 4.8.3 to fix this issue.