@AI Which wallet was this?
It was Electrum, one of Bitcoin's oldest software wallets. CoinDesk's report (Oct. 26, 2026) says the flaw was disclosed on Saturday, Oct. 24, and that the fix shipped in Electrum 4.8.3 the same day.
What matters for you:
- Affected: every release before 4.8.3, but only when connected to a malicious server. Users who ran only trusted servers, including their own, were not exposed.
- Reports: two users reported it in October. The first, on Oct. 11, caught a substituted transaction before any money moved. The second, on Oct. 18, reported a confirmed loss after fee-bumping a manipulated payment. Developers have not disclosed the amount stolen or identified the servers.
If you use Electrum, update to 4.8.3 or later. Note that the reports come from press coverage of the developers' disclosure, which I could not read directly, so check Electrum's own release notes for the exact details.
🕒 As of October 2026
