--- title: "Electrum patches flaw that let rogue servers redirect fee-bumped payments" description: "Electrum released version 4.8.3 to fix a high-severity flaw affecting all earlier versions, Decrypt reported. A compromised server could hide a pending payment and inject a fake conflicting transaction so that a user's fee bump paid an attacker; the developer advisory said some servers were running…" language: en canonical: "https://whycoinmoves.com/en/events/bitcoin-bitcoin-wallet-fixes-critical-flaw-6d889edc905778" published: 2026-10-26T17:45:01.000Z updated: 2026-10-26T18:46:03.000Z indexable: true --- # Electrum patches flaw that let rogue servers redirect fee-bumped payments Electrum released version 4.8.3 to fix a high-severity flaw affecting all earlier versions, Decrypt reported. A compromised server could hide a pending payment and inject a fake conflicting transaction so that a user's fee bump paid an attacker; the developer advisory said some servers were running… Attributed sources: [Decrypt]() ## Key facts Electrum released version 4.8.3 to fix a high-severity flaw affecting all earlier versions, Decrypt reported. A compromised server could hide a pending payment and inject a fake conflicting transaction so that a user's fee bump paid an attacker; the developer advisory said some servers were running the attack in the wild, with one user reporting a confirmed loss. Evidence strength: Single source, 1 publisher group(s) (Decrypt). After site detection, observed returns were 5 minutes: -0.12% (26/10/2026, 17:45 → 26/10/2026, 17:50, UTC; Gate · USDT); 1 hour: -0.13% (26/10/2026, 17:45 → 26/10/2026, 18:45, UTC; Gate · USDT) In the preceding 30 days, the 99th percentile of absolute hourly returns was 1.01% (OKX · USDT; cutoff 26/10/2026, 17:45, UTC). ## Returns after site detection | Window | Return | BTC | Difference from BTC | Actual sampled interval (UTC) | Source | | --- | --- | --- | --- | --- | --- | | 5 minutes | -0.12% | -0.12% | 0.00 pp | 26/10/2026, 17:45 → 26/10/2026, 17:50 | Gate · USDT | | 1 hour | -0.13% | -0.13% | 0.00 pp | 26/10/2026, 17:45 → 26/10/2026, 18:45 | Gate · USDT | ## Historical hourly baseline | Metric | Value | | --- | --- | | Coverage | 100.0% (720/720) | | Median absolute hourly return | 0.14% | | 99th percentile of absolute hourly returns | 1.01% | | BTC beta | 1.00 | | Source / cutoff (UTC) | OKX · USDT / 26/10/2026, 17:45 | ## Claims and open questions - Decrypt reported that the flaw affects all Electrum versions before 4.8.3, which verifies cryptographic signatures on wallet-owned inputs before adding unconfirmed transactions to local history. - Electrum developer SomberNight's advisory states that some servers are performing this attack in the wild, backed by two user reports, including a confirmed loss reported by a user identified as Raju-K12 after a fee bump on October 18. - Decrypt reported that the fix was tagged in the repository on October 23 and binaries were published the following day, while incoming transactions from external senders are still accepted without signature verification. - How much was lost in the confirmed case reported by Raju-K12? An on-chain transaction record or an updated developer advisory would establish the amount. - When will signature verification be extended to incoming transactions from external senders? An official Electrum advisory or release note would confirm the timeline. ## Source evidence - [Bitcoin Wallet Fixes Critical Flaw That Redirected Funds to Attackers]() — Decrypt; published 26/10/2026, 17:41; received 26/10/2026, 17:45 (UTC). ## Recent BTC events and market reactions - [South Korea weighs fourth delay of 22% crypto tax to 2029]() — Published 26/10/2026, 14:06 (UTC) · Single source (1 publisher) · General news · 5m +0.31% / 1h +0.98% - [Strategy pauses bitcoin purchases, spends $204.9 million buying back STRC]() — Published 26/10/2026, 13:23 (UTC) · Multiple publishers (4 publishers) · General news · 5m -0.24% / 1h -0.03% - [Bitcoin Magazine video examines Bitcoin exposure after PHP flaws take sites offline]() — Published 26/10/2026, 13:21 (UTC) · Single source (1 publisher) · Security · 5m -0.30% / 1h +0.12% - [Bitcoin slips below $80,000 as tech sell-off and ETF outflows weigh ahead of Fed]() — Published 26/10/2026, 13:02 (UTC) · Multiple publishers (2 publishers) · Market watch · 5m -0.07% / 1h -0.72% - [Galaxy Research says bitcoin's bear market ended at the June low]() — Published 26/10/2026, 13:01 (UTC) · Multiple publishers (3 publishers) · Market watch · 5m -0.09% / 1h -0.72% - [Full coin archive]() ## Research for this archive - [Crypto hacks and price impact: Bybit and Cetus case studies]() - [Why is crypto moving? How to check the evidence behind a price explanation]() - [Altcoin beta to Bitcoin: BTC, ETH, SOL and DOGE hourly returns]() - [Will Bitcoin go back up? Every crash since 2011 and its recovery time]() Evidence levels describe source coverage, not the probability that a report is true. Price moves and their timing cannot establish a cause; minute samples show an observed interval and alert thresholds are heuristics. Explanations are model-assisted, with citations and figures checked. Source titles stay in their original language; full articles are not republished. [Methods and limitations]()