Electrum

Electrum before 4.7.2 contains a spending limit bypass vulnerability in the Nostr Wallet Connect plugin that allows malicious NWC clients to exceed daily_limit_sat by exploiting non-atomic budget checks and millisatoshi truncation. Attackers can send concurrent pay_invoice requests that pass budget_allows_spend() before add_to_budget() runs, or repeatedly pay msat amounts that are floored to whole satoshis, to drain funds beyond the limit.

Published: 2026-10-27T13:09:52.728Z
Updated: 2026-11-02T16:01:22.924Z

Electrum 4.6.0 before 4.7.2 contains an authorization bypass in the external plugin loader, which executes a plugin's __init__.py module when the plugin is marked enabled in the config file, without verifying its plugin-password signature. A rogue local process with write access to the Electrum data directory can place plugin code in the plugins/ folder and mark it enabled, causing arbitrary code execution inside the Electrum process.

Published: 2026-10-27T13:09:52.040Z
Updated: 2026-11-05T16:59:57.475Z

Electrum before 4.8.3 fails to verify signatures of wallet-owned inputs in unconfirmed mempool transactions, allowing malicious servers to replace a just-broadcast transaction with a conflicting one. Attackers can swallow the user's transaction and display an invalid zero-fee copy paying an attacker address, tricking users into RBF fee-bumping and signing it.

Published: 2026-10-27T13:09:51.347Z
Updated: 2026-10-28T16:16:43.752Z