- Hackers from the TeamPCP group used a malicious version of the popular Nx Console extension to take control of a GitHub employee’s device.
- The incident led to the leak of approximately 3,800 internal repositories, including fragments of service requests from customers.
- The attack lasted just 18 minutes, which was enough time to download password-stealing tools from managers and cloud configurations.
The official security announcement confirmed the worst-case scenario for developers. GitHub fell victim to a precisely planned attack on the software supply chain, which began with the takeover of the private computer of one of the developers of the Nx Console extension for Microsoft Visual Studio Code. Criminals used this device to inject malicious code into an official tool used around the world. The result was complete compromise of the company’s equipment belonging to an employee of the GitHub platform.
The situation is a direct result of a previous security incident that affected the TanStack ecosystem.
Narwhal Technologies co-founder Jeff Cross admitted to X that the plugin code was violated nrwl.angular-console occurred after their own programmer’s security was breached. However, the avalanche moved much wider. At the same time, similar problems were reported by other global entities, including OpenAI, Mistral AI and Grafana Labs.
1/ We are sharing additional details regarding our investigation into unauthorized access to GitHub’s internal repositories. Yesterday we detected and contained a compromise of an employee device involving a poisoned VS Code extension. We removed the malicious extension version,
How the GitHub attack and data leak happened
Cybercriminals operating under the name TeamPCP managed to quickly copy and extract approximately 3,800 internal code repositories from the systems. Alexis Wales, director of information security at GitHub, issued a statement categorically assuring that there is no evidence of a leak of customer data stored outside the infected area. The threat does not directly affect external repositories of organizations or private enterprises using the platform. However, internal resources contained sensitive records of technical conversations with development support.
Modern security systems require immediate response in such situations.
GitHub implemented environment isolation procedures and conducted mass revocation of key secrets and authentication tokens. Systems are constantly monitored for unusual activity.
A trap hidden in the Visual Studio Marketplace
The infected version of the extension was available for download on May 18, 2026 for exactly 18 minutes, between 12:30 and 12:48 UTC. Nir Zadok, a researcher from OX Security, points to the extremely high level of technical refinement of this operation. The extension worked fine, but it invoked a single system command in the background. The command masqueraded as a routine MCP configuration task, downloading a malicious package from a hidden commit in the project’s official GitHub code.
This short period of time was enough for hackers to infect systems with credential stealer software. The tool was designed specifically to search specific locations. The targets were 1Password password databases, Anthropic Claude Code configuration files, as well as access data to the npm and Amazon Web Services platforms.
Automatic updates as a threat to GitHub infrastructure
The operation of TeamPCP is based on a repeatable pattern. Compromising one trusted tool allows it to harvest credentials from the hardware of the developers who downloaded them. The same access keys are then used to break the security of the next, completely legal software in the chain.
