Electrum: Spending limit bypass in Nostr Wallet Connect plugin
Summary
Electrum before 4.7.2 contains a spending limit bypass in the Nostr Wallet Connect (NWC) plugin. A malicious or compromised NWC client with an existing connection can send concurrent payment requests that pass the budget check before the budget is updated, or repeat payments in millisatoshi amounts that are rounded down to whole satoshis. This allows the client to spend funds beyond the configured daily limit. An attacker needs a valid NWC connection created by the wallet owner.
Affected
- Electrum versions below 4.7.2 with the NWC plugin enabled (the CVE record lists 0 to < 4.7.2; the vendor advisory lists 4.6.0 to < 4.7.2, as the plugin was added in 4.6.0)
Fixed in
- Electrum 4.7.2 or later (upstream fix commits 3956bff and 5222374)
Workaround
- No vendor workaround is documented.
- Until the update is applied, remove unused NWC connections, rotate NWC secrets and keep daily limits low.
- Third-party hardening suggestions (not verified by the vendor): require approval for new connections and add a second spending limit at the payment-service boundary.
Exploitation
- OffSeq reports the CVE as not known to be exploited.
- No public proof of concept was found.
- Exploitation in the wild: unknown, the CVE is only days old.
Our recommendation
- Check whether any Electrum installation has the NWC plugin enabled and note its version.
- Upgrade all installations below 4.7.2 to the current upstream release.
- Rotate NWC secrets and remove unused or unknown NWC connections.
- Monitor payment logs for transactions beyond the expected limit.
- Re-check NVD and CISA once the record has been analysed.
Public exploits
PoC-in-GitHub, Metasploit and Exploit-DB list nothing for this CVE.
Research sources
- GitHub Security Advisory GHSA-q7m2-785w-r585 github.com
- VulnCheck advisory www.vulncheck.com
- Fix commit 3956bff github.com
- Fix commit 5222374 github.com
- OffSeq threat radar radar.offseq.com
- Ubuntu security notice ubuntu.com
- Strix CVE overview www.strix.ai
Researched and written up in English and German by an AI (Claude by Anthropic) based on NVD, CISA, EPSS and the sources listed. The vendor information is authoritative. Researched on 31 Oct 2026, 00:35.
Original description (NVD)
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.
NVD references (4)
- 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-b…
Sources
The tracker combines official, freely usable data sources – updated continuously:
- NVD (NIST) – CVEs, rating (CVSS), affected products
- CISA KEV – vulnerabilities confirmed by CISA as actively exploited
- CISA Vulnrichment – CISA assessment (SSVC) in the official CVE record
- FIRST EPSS – probability of exploitation
- Microsoft MSRC – Patch Tuesday: vulnerabilities, severity, updates
- PoC-in-GitHub – public proof-of-concept repositories
- Metasploit (Rapid7) – modules of the Metasploit Framework
- Exploit-DB (OffSec) – archive of public exploits (links only)
- Patch days: official vendor pages (linked per vendor) (Vendor patch days)
This product uses data from the NVD API but is not endorsed or certified by the NVD. EPSS data © FIRST.org.
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