CVE-2026-117603criticalCWE-367

CVE-2026-117603: critical vulnerability in spesmilo electrum

Electrum before 4.7.2 Nostr Wallet Connect Plugin Daily Spending Limit Bypass

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28Vexday Risk Score

No sign of exploitation. No public exploitation artifact known so far.

ssvc Trackcvss 9.3epss 0.2%
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.
CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:H/VI:H/VA:H/SC:N/SI:N/SA:N
Affected products
spesmilo · electrum
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In the same product, most dangerous first.

CVE-2026-117601CRITICALElectrum before 4.8.3 Missing Signature Verification of Mempool TransactionsEPSS 0.2%CVE-2026-117602HIGHElectrum before 4.7.2 External Plugin Authorization Bypass Local Code ExecutionEPSS 0.1%