600+ npm Packages Hit in Mini Shai-Hulud Supply Chain Attack

On May 19, 2026 a sophisticated supply-chain worm rapidly compromised hundreds of npm package versions (Socket/Endor Labs observed 600+ in one wave and 1,055 versions across 502 packages across ecosystems) by injecting obfuscated preinstall payloads and phantom-commit optionalDependencies; the implant daemonizes, harvests cloud and CI credentials (IMDSv2, ECS metadata, GCP keys, Vault tokens, GitHub OIDC), persists outside node_modules, exfiltrates data to filev2.getsession.org and GitHub repositories, and abuses Sigstore to produce cryptographically valid provenance attestations that make malicious packages appear legitimate.