npm Worm Shai-Hulud Ran Malicious Code Simply by Developers Opening a Folder

In August 2026, attackers compromised a GitHub account belonging to a maintainer of widely used npm caching libraries and injected malicious code directly into the project's release pipeline. Because the packages were published via the project's own legitimate automation, they carried valid provenance signatures, allowing the payload to spread to hundreds of packages within roughly four hours. Crucially, the malware executed not through npm install but via editor and agent configuration files — such as .vscode/tasks.json and .claude/settings.json — that trigger commands automatically when a folder is opened. Once active, the worm harvested credentials from developer environments, CI systems, and cloud configurations, then used stolen tokens to propagate itself across other packages and repositories. The incident highlights a critical gap in supply chain security: provenance signing verifies the build path but cannot confirm whether the source code committed to the pipeline was itself trustworthy.