GitHub Confirms TeamPCP Hack of Internal Environment
GitHub confirmed that TeamPCP hackers breached a limited internal environment connected to the broader TanStack supply-chain campaign. While customer repositories and production systems remained secure, the incident raised concerns over software supply-chain integrity and developer platform security. The threat actor group TeamPCP claimed responsibility for stealing approximately four thousand developer code repositories and intended to sell the stolen internal source code.
Signal context
First seen: May 20, 2026
Last updated: Jun 29, 2026
Status: Public signal
Key points
- GitHub confirmed a breach of a limited internal environment by TeamPCP hackers.
- The incident was linked to the broader TanStack supply-chain campaign.
- Approximately 4,000 developer code repositories were allegedly stolen.
Signal analysis
BetaThis analysis groups the signal by industry, likely incident action and impacted security area. It helps compare this signal with other published signals without treating the labels as final determinations.
Sector: Information
Likely country: Location not provided
Watch internet-facing systems, credential abuse and exploit activity.
- Source type: outside the affected organization
Impact area: Confidentiality, Integrity
Likely asset: User or customer data
- 26 signals in the same sector
- 90 signals with the same likely impact area
- 1 signal linked to this organization/domain
External sources
Biggest Cyber Attacks, Data Breaches, Ransomware Attacks of May 2026https://www.cm-alliance.com/cybersecurity-blog/biggest-cyber-attacks-data-breaches-ransomware-attacks-of-may-2026Public source from cm-alliance.com.
Data Breach Tracker 2026: Latest Breaches and Settlements - Redfox Cybersecurityhttps://www.redfoxsec.com/blog/data-breach-tracker-2026-latest-breaches-settlementsPublic source from redfoxsec.com.
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