Incident Overview
Two Electrum wallet users reported Bitcoin theft, one user lost 1,400 BTC due to a malicious update.
Two users of the Electrum wallet have reported their Bitcoin holdings stolen. One of the users suffered a significant loss of 1,400 BTC. The user installed an old version of the Electrum wallet and when attempting to transfer about 1 BTC, a pop-up appeared stating a security update was required before proceeding.
After installing the prompted update, the entire balance of the user was immediately transferred to a scammer's address.
Incident Report
Protocol Information
What the Attacker Needed to Succeed
Understanding the prerequisites for this type of attack helps auditors identify protocols that are most at risk and helps developers build better defenses.
What Auditors Should Check
If you're auditing a protocol with similar architecture to Electrum, these are the critical security checks that could have prevented this incident (August 2020).
- Verify all logic paths related to Access Control are guarded by proper access controls and input validation - see the Access Control Attacks attack class for patterns
- Review privileged functions (owner, admin, governance) for potential abuse vectors - centralization risks should be documented and bounded with timelocks or multi-sigs
Master these auditing techniques with hands-on labs and real exploit scenarios in the Smart Contract Hacking course.
Free TrialSecurity Audit History
- Audit Report 1 Report
Related Attack Classes
The technique used in this hack maps to these vulnerability classes in our security curriculum:
Sources & References
Learn to Prevent the Next Electrum
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