Microsoft disables 73 GitHub repos after malware breach

Microsoft has disabled access to more than 70 of its own open-source repositories on GitHub after hackers compromised them with malware designed to steal user credentials. The incident, which came to light in early June 2026, affected projects across four of Microsoft's GitHub organizations, including Azure, AzureSamples, microsoft, and MicrosoftDocs.

Security researchers from Cloudsmith and the community-driven site OpenSourceMalware first flagged the breach. They reported that the malware, a variant known as the Miasma worm, was configured to harvest passwords and other sensitive data when developers opened the compromised code in popular AI coding applications such as Claude Code, Gemini's command line interface, Cursor, or Visual Studio Code. The attack rendered numerous automated workflows inoperable; for example, any process referencing the compromised "Azure-functions-action-v1" repository ceased to function.

A Microsoft spokesperson, Ben Hope, confirmed the company had temporarily removed the repositories while investigating potential malicious content. He stated that some repositories have been restored after review, while others remain offline. The company has also...