GitHub is investigating a significant security incident after a hacking group known as TeamPCP claimed it had gained access to the company’s internal repositories and source code.

The threat group allegedly listed the stolen data for sale on a cybercrime forum earlier this week, claiming the leak includes nearly 4,000 private repositories connected to GitHub’s internal systems. Reports suggest the attackers were demanding at least $50,000 for the dataset and threatened to release it publicly if no buyer was found.

GitHub, which is owned by Microsoft, confirmed that it detected unauthorized access involving its internal repositories. However, the company stated that there is currently no evidence indicating customer repositories or enterprise data were compromised.

Employee Device Reportedly Compromised

In an update shared on X, GitHub revealed that investigators traced the breach back to a compromised employee device. According to the company, the incident involved a malicious Microsoft Visual Studio Code extension that allowed attackers to gain access.

GitHub said it immediately isolated the affected endpoint, removed the harmful extension, and began its internal incident response process. The platform also confirmed that it rotated critical secrets and credentials as a precautionary measure.

The company noted that the attackers’ claims regarding approximately 3,800 repositories being accessed appear to align with its ongoing investigation.

TeamPCP Behind the Attack

The breach has been linked to TeamPCP, a hacking group known for targeting software supply chains and open-source ecosystems.

Cybersecurity researchers have previously connected the group to attacks involving tools and packages such as LiteLLM, Trivy Vulnerability Scanner, and Checkmarx. The group is also reportedly tracked by Google Threat Intelligence under the identifier UNC6780.

Screenshots shared online allegedly show TeamPCP advertising GitHub’s source code and internal organizational data for sale. The group claimed it was not attempting to extort GitHub directly and suggested the data could eventually be leaked publicly if a buyer was not found.

The attackers also reportedly published repository archive names and partial screenshots as proof of the breach.

Security Researchers Warn of Wider Risks

Experts warn that access to GitHub’s internal repositories could create serious cybersecurity concerns if the stolen code falls into the wrong hands.

Attackers may attempt to analyze internal source code for vulnerabilities, security weaknesses, or infrastructure details that could later be exploited in broader attacks targeting developers or software supply chains.

Researchers are also monitoring connections between this breach and a growing malware campaign linked to TeamPCP.

Malicious Python Package Campaign Expands

Around the same time, cybersecurity firms identified malicious versions of the official Microsoft Durable Task Python package on PyPI. Researchers believe the compromise may have originated from credentials stolen during previous attacks.

According to reports from security companies, the malicious package versions contained malware capable of stealing credentials from cloud services, password managers, SSH keys, Docker environments, VPN configurations, and developer tools.

The malware reportedly targeted Linux systems and included self-propagation features capable of spreading across AWS EC2 environments and Kubernetes clusters.

Some researchers described the campaign as an evolution of TeamPCP’s earlier “Mini Shai-Hulud” malware operation, which focused heavily on software supply chain compromise techniques.

GitHub Continues Investigation

GitHub says it is continuing to investigate the incident and monitor its infrastructure for any additional malicious activity.

The company added that affected customers would be notified through official incident response channels if investigators discover any impact beyond GitHub’s internal repositories.



A detailed report is expected once the investigation is completed.