CVE-2026-117603
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.
Does this matter?
High impact if exploited, but EPSS currently rates exploitation as unscored. Schedule it in the normal patch cycle and watch for a rise in EPSS or a public exploit.
Description
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
- 9.3 CRITICALCVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:H/VI:H/VA:H/SC:N/SI:N/SA:N/E:X/CR:X/IR:X/AR:X/MAV:X/MAC:X/MAT:X/MPR:X/MUI:X/MVC:X/M
- EPSS
- No score yet
- Public exploits
- None in Exploit-DB
- CISA KEV
- Not listed
- Weakness
- CWE-367
- Source
- disclosure@vulncheck.com
References
- https://github.com/spesmilo/electrum/commit/3956bff0684f6060fbe8c823c3ee921928cdcaa5
- https://github.com/spesmilo/electrum/commit/5222374046d2a92da371d46c79ce0e61e7e2a42d
- https://github.com/spesmilo/electrum/security/advisories/GHSA-q7m2-785w-r585
- https://www.vulncheck.com/advisories/electrum-before-4.7.2-nostr-wallet-connect-plugin-daily-spending-limit-bypass
Source: NVD record, EPSS from FIRST.org, KEV from CISA, exploits from Exploit-DB. Refreshed daily. Download this record as JSON.