Mini Shai-Hulud Self-Spreading npm Supply Chain Worm

The TeamPCP threat group has launched a sophisticated, self-propagating supply chain attack known as 'Mini Shai-Hulud,' targeting prominent npm ecosystems including TanStack, Mistral AI, and UiPath. By exploiting 'pull_request_target' vulnerabilities and poisoning GitHub Actions caches, the attackers extracted OIDC tokens to publish over 370 malicious package versions directly to the npm registry. These packages carry valid SLSA Build Level 3 provenance, significantly complicating traditional verification methods.

The technical core of the attack is a 2.3 MB obfuscated JavaScript payload (router_init.js/tanstack_runner.js) designed to harvest a massive range of credentials from CI/CD runners and developer workstations. It specifically targets GitHub, npm, AWS, Kubernetes, and HashiCorp Vault secrets. Notably, the worm reads GitHub Actions runner memory to extract masked secrets and implements persistence via Claude Code and VS Code hooks to survive reboots and environment cleans.

This campaign represents a critical risk to the software supply chain as it weaponizes legitimate build infrastructure to infect downstream dependencies. Organizations using affected packages must treat all secrets accessible in those environments as compromised. The attacker has also included a ransom threat, claiming that revoking stolen npm tokens will trigger a destructive wipe of the infected host, necessitating careful forensic isolation before remediation.