GMX

The decentralized exchange GMX experienced a $42 million theft due to a vulnerability in its platform. The hacker exploited a bug, stealing cryptocurrency worth $42 million. After negotiations, the hacker returned the stolen funds in exchange for a $5 million bounty. GMX assured users that their funds would be restored using bug bounty reserves. The vulnerability was later fixed, and the platform provided a detailed post-mortem. Despite the resolution, the hacker could still face legal consequences if identified, as seen in a similar case involving Mango Markets.

Source: https://therecord.media/hacker-returns-stolen-gmx-bounty

TPRM report: https://www.rankiteo.com/company/gmx-capital

"id": "gmx911080725",
"linkid": "gmx-capital",
"type": "Vulnerability",
"date": "7/2025",
"severity": "50",
"impact": "2",
"explanation": "Attack limited on finance or reputation"

{'affected_entities': [{'industry': 'Cryptocurrency',
                        'name': 'GMX',
                        'size': '714,000 users',
                        'type': 'Decentralized Exchange'}],
 'attack_vector': 'Exploit of a vulnerability in the platform',
 'date_detected': '2023-09-06',
 'date_publicly_disclosed': '2023-09-06',
 'date_resolved': '2023-09-08',
 'description': 'A hacker stole $42 million from the decentralized exchange '
                'GMX and returned the funds in exchange for a $5 million '
                'bounty.',
 'impact': {'brand_reputation_impact': 'Potential reputational damage',
            'financial_loss': '$42 million initially stolen',
            'legal_liabilities': 'Possible legal liability for the hacker if '
                                 'identified'},
 'investigation_status': 'Resolved',
 'motivation': 'Financial gain',
 'post_incident_analysis': {'corrective_actions': 'Bug resolved in recent '
                                                  'updates to the platform',
                            'root_causes': 'Bug in the GMX platform'},
 'references': [{'source': 'Blockchain security companies'}],
 'regulatory_compliance': {'legal_actions': 'Possible legal action against the '
                                            'hacker'},
 'response': {'communication_strategy': 'Public statements and blockchain '
                                        'messages',
              'incident_response_plan_activated': True,
              'recovery_measures': 'Funds returned by the hacker',
              'remediation_measures': 'Bug resolved in recent updates to the '
                                      'platform'},
 'threat_actor': 'Unidentified hacker',
 'title': 'GMX Decentralized Exchange Cryptocurrency Theft',
 'type': 'Cryptocurrency Theft',
 'vulnerability_exploited': 'Bug in the GMX platform'}