Electrum wallet vulnerable before version 4.8.3: what you can do now

The information provided in this article is for informational purposes only and does not constitute financial advice. Cryptocurrency investments carry a high degree of risk. Always conduct your own research.Electrum released version 4.8.3 on October 23, 2026 and closed a flaw that malicious servers had already exploited. It does not harvest your keys; it targets the moment you speed up a stuck transaction.Anyone keeping bitcoin in Electrum should check their wallet's version number today. Every release before 4.8.3 carries a flaw through which a malicious server can get you to sign a payment to an attacker. The developers closed it on October 23, 2026 and disclosed it a day later. Their security advisory contains the sentence that separates this case from a theoretical weakness: some servers are already carrying out this attack. The flaw is rated high in severity and carries no CVE number. What is remarkable is not its technique but its lever: it does not harvest your keys and breaks no encryption. It waits for you to speed up a stuck transaction, one of the most common moves in everyday bitcoin use. What Electrum 4.8.3 fixes: signatures for your own inputs are checked Electrum is ...