A new variant of the Shai‑Hulud npm worm, dubbed ChainDrop, has infected 444 packages and is downloaded about 2 billion times per month.

Security researchers identified the campaign on August 4. The worm spreads through tarball files rather than direct repository commits, allowing it to evade typical source‑code scanning.

Once executed, ChainDrop searches for npm tokens with full write privileges, cloud keys, and GitHub credentials. It can harvest these secrets from shell configurations, environment variables, or live memory, encrypt them, and send them to attacker‑controlled servers. If an npm token is found, the malware downloads the tarballs of all packages the token can modify, rebuilds the archive to include its payload, and reinfects other packages.

The worm also looks for GitHub credentials. When found, it queries the GitHub API for repositories and branches, then commits malicious configuration files directly into those branches. Opening an infected branch in tools such as VS Code or Claude Code can trigger the malicious setup.

Because npm is commonly used in automated CI/CD pipelines, the worm can infiltrate fresh builds, increasing its reach. Researchers advise checking for unexpected .vscode/tasks.json and .claude/settings.json files, reviewing all branches, and auditing GitHub Actions workflows. They recommend treating repository‑supplied configuration as executable and updating trusted publishing tools.

SafeDep has published a list of the compromised packages and version numbers for verification. Ongoing analysis will determine whether additional supply‑chain gaps exist.