Electrum 4.8.3 Fixes Exploited Bug: Bitcoin at Risk When Bumping Fees
BTC when published $80,791Now $80,595 ▼ −0.24% since it was published
Electrum users who try to speed up a stuck Bitcoin transaction may unknowingly sign a payment to an attacker. On October 24, 2026, the Electrum development team published security advisory GHSA-6jp4-8v48-cc5v alongside version 4.8.3, describing how a malicious server can replace a just-sent transaction with a fraudulent one and wait for the user to bump the fee via Replace-by-Fee. Two reports reached the developers before the patch shipped; one involved a confirmed loss of funds. We reviewed the advisory published on GitHub by developer SomberNight, the official Electrum website and its FAQ, and coverage by The Defiant and The Crypto Basic. The advisory does not disclose the amount lost or the number of malicious servers involved.
First reported by Spaziocrypto. This page is a short excerpt; the full text is theirs.
