CVE-2026-117603
MediumCVSS 4.3Exploitation Probability (EPSS)
Low risk9th percentile - higher than 9% of all known CVEs
Summary
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.
Risk Assessment
Attackers can send concurrent payment requests or repeatedly pay msat amounts to drain funds beyond the limit.
Recommendation
Update Electrum to version 4.7.2 or later.
Other vulnerabilities in Electrum
See all- CVE-2026-117602High
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.
- CVE-2026-117601High
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.
Original NVD description (English source)
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.
Vulnerability data from NVD (NIST) · CISA KEV · EPSS