Incident Overview
An EOA 0x84a25fB2…646fcB was exploited via a phishing attack on the Arbitrum network. The current losses reached 4,000,000 USD.
An EOA wallet was compromised or exploited via a phishing attack. Firstly the victim called signalTransfer() function on the GMX: Reward Router and funded the exploiter with ETH. After this, the malicious actor transferred the pending assets of the victim from the GMX: Reward Router and unstaked them.
All stolen GMX tokens were swapped to the ETH and bridged to another EOA on the Ethereum network.
Scammer addresses:
https://arbiscan.io/address/0x4008f610…f7f9d8
https://etherscan.io/address/0x956A0412…647946
Phishing TX:
https://arbiscan.io/tx/0xe84e0fbc…732184
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 GMX Phishing, these are the critical security checks that could have prevented this incident (January 2023).
- Verify all logic paths related to Phishing are guarded by proper access controls and input validation - see the Phishing 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 TrialRelated Attack Classes
The technique used in this hack maps to these vulnerability classes in our security curriculum:
Sources & References
Learn to Prevent the Next GMX Phishing
The GMX Phishing hack is one of many attacks that skilled auditors are trained to detect before deployment. Master real exploit patterns and defense techniques with hands-on Web3 security training.