70 Microsoft GitHub Repos Disabled After Hackers Inject Password-Stealing Malware

Microsoft owns GitHub. Microsoft’s own open-source repos on that platform just got pwned — and the malware was designed to steal passwords from AI developers. At least 70 projects are now disabled, with a notice reading “Access to this repository has been disabled by GitHub Staff due to a violation of GitHub’s terms of service.”

The Attack Targeted Tools AI Developers Actually Use

Security researchers at Cloudsmith and community analysts at OpenSourceMalware caught the injection. The malware specifically targeted credentials when a developer opened the compromised tools inside apps like Claude Code, Gemini’s command-line interface, and VS Code. These aren’t random libraries — they’re the daily drivers for anyone building on Azure or using Microsoft’s AI toolchains.

A Microsoft spokesperson acknowledged receipt of the inquiry but declined immediate comment. The repos remain locked down as of publication.

A Supply-Chain Shot That Hit the Supply Chain’s Landlord

Supply-chain attacks on open-source projects are common — lone maintainers get phished, creds get stolen, malicious commits slip in. It’s rare for a company with Microsoft’s security budget and GitHub ownership to get hit on its own code. That’s exactly what happened here, and this isn’t the first time in recent weeks.

According to Ars Technica, Microsoft’s Durable Task project — a tool for building distributed apps — was compromised in mid-May. OpenSourceMalware now describes this latest incident as a “re-compromise” of that same project. Either Microsoft didn’t fully clean the initial breach, or the attackers found a new way back in. Either explanation is worse than the other.

What This Means for Anyone Running AI Dev Tooling

If you downloaded any Microsoft open-source tool — especially anything tied to Azure, Durable Task, or AI coding assistants — since mid-May, assume the binary you ran may have shipped with credential stealers. The number of affected downloads is unknown, but the exposed surface is large: dozens of repos, each potentially cloned thousands of times.

The sobering takeaway is that even the company that hosts the world’s largest open-source code repository can’t keep its own supply chain clean. Expect more detailed security advisories from Microsoft once the investigation concludes.

Source: Microsoft's open source tools were hacked to steal passwords of AI developers
Domain: techcrunch.com