A self-replicating “Miasma” worm has been reported to reach 73 Microsoft GitHub repositories, further escalating an ongoing supply chain attack campaign. Multiple outlets cite OpenSourceMalware data indicating the compromise affects repositories across four Microsoft-owned GitHub organizations: Azure, Azure-Samples, Microsoft, and MicrosoftDocs. The reports say the worm plants malicious code intended to harvest developer credentials, targeting the software development workflow.
In response, GitHub disables access to the affected repositories. While the incident is described as part of a wider, previously observed campaign against open-source ecosystems, the Microsoft repository impact is presented as a major escalation. The coverage does not specify which individual repositories or commits are affected, but it frames the action by GitHub as a containment step to limit further spread and reduce the risk that harvested credentials could be used to compromise accounts or downstream systems.
The incident highlights how supply chain threats can propagate through repository-level access and automated tooling. Authorities and affected maintainers continue to assess the scope and follow mitigation steps directed at the compromised repositories.
