GitHub: Cyber Security News ®’s Post

GitHub Confirms Internal Source Code Breach by TeamPCP Threat Actor

A cybercriminal group known as TeamPCP has claimed responsibility for breaching GitHub’s internal systems, allegedly stealing proprietary data, including source code from approximately 4,000 private repositories. The threat actor announced the breach via a post on X (formerly Twitter), asserting access to sensitive internal assets tied to GitHub’s core platform.

GitHub acknowledged the incident in a public statement, confirming unauthorized access to its internal repositories while emphasizing that customer data remains unaffected. The company is actively investigating the scope and impact of the breach.

The incident highlights ongoing risks to software supply chains, as threat actors increasingly target development environments to exploit vulnerabilities or extract intellectual property. No further details on the attack vector or potential motives have been disclosed.

Source: https://www.linkedin.com/feed/update/urn:li:activity:7462703232449126401

GitHub cybersecurity rating report: https://www.rankiteo.com/company/github

"id": "GIT1779251025",
"linkid": "github",
"type": "Breach",
"date": "5/2026",
"severity": "85",
"impact": "3",
"explanation": "Attack with significant impact with internal employee data leaks"

{'affected_entities': [{'customers_affected': 'No customer data affected',
                        'industry': 'Technology',
                        'name': 'GitHub',
                        'type': 'Company'}],
 'customer_advisories': 'Customer data remains unaffected',
 'data_breach': {'number_of_records_exposed': 'Approximately 4,000 private '
                                              'repositories',
                 'personally_identifiable_information': 'None (customer data '
                                                        'unaffected)',
                 'sensitivity_of_data': 'High (internal assets tied to '
                                        'GitHub’s core platform)',
                 'type_of_data_compromised': 'Source code, proprietary data'},
 'description': 'A cybercriminal group known as TeamPCP has claimed '
                'responsibility for breaching GitHub’s internal systems, '
                'allegedly stealing proprietary data, including source code '
                'from approximately 4,000 private repositories. The threat '
                'actor announced the breach via a post on X (formerly '
                'Twitter), asserting access to sensitive internal assets tied '
                'to GitHub’s core platform. GitHub acknowledged the incident '
                'in a public statement, confirming unauthorized access to its '
                'internal repositories while emphasizing that customer data '
                'remains unaffected. The company is actively investigating the '
                'scope and impact of the breach.',
 'impact': {'data_compromised': 'Proprietary data, including source code from '
                                'approximately 4,000 private repositories',
            'systems_affected': 'Internal repositories'},
 'investigation_status': 'Ongoing',
 'references': [{'source': 'X (formerly Twitter)'}],
 'response': {'communication_strategy': 'Public statement acknowledging the '
                                        'breach'},
 'threat_actor': 'TeamPCP',
 'title': 'GitHub Internal Source Code Breach by TeamPCP Threat Actor',
 'type': 'Data Breach'}