Incident Overview
On June 9, 2024, Loopring Smart Wallets suffered a security breach where attackers exploited the Recovery process for wallets that had only one Guardian, specifically the Loopring Official Guardian. By compromising Loopring's 2FA service, the attackers were able to impersonate wallet owners, gain approval from the Official Guardian, and reset wallet ownership to steal assets. Loopring has paused Guardian and 2FA-related functions, and is working with Mist security experts, SlowMist, and law enforcement to investigate.
The attacker’s strategy focused on wallets with single-guardian setups, particularly those where the Loopring Official Guardian was the sole protector. By breaching Loopring’s 2FA system, the hacker bypassed ownership verification and falsely initiated wallet Recovery. This gave them control of the wallets, enabling them to withdraw assets to two addresses:
The 2FA compromise appears to be the core vulnerability, allowing the attacker to impersonate users during the Guardian approval process. After identifying the breach, Loopring halted Guardian and 2FA-related features, stopping further unauthorized recoveries. Investigations are ongoing with SlowMist and law enforcement, and Loopring has pledged to update the community as more details emerge.
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 Loopring, these are the critical security checks that could have prevented this incident (June 2024).
- Verify all logic paths related to Guardian 2FA service exploit / 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
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