TanStack Npm Packages Compromised Inside The Mini Shai Hulud Supply Chain Attack

Snyk reports a multi-part supply-chain campaign dubbed “Mini Shai-Hulud” (April–May 2026) that compromised 84 npm artifacts across 42 @tanstack/* packages (and several other namespaces) by chaining a GitHub Actions “Pwn Request,” cache poisoning, and OIDC token extraction from runner memory. The attacker produced malicious releases that carried valid SLSA Build Level 3 attestations — the first known npm supply-chain compromise with valid attestations — and delivered a Bun-based credential stealer (also observed in a malicious PyPI lightning release) that exfiltrates credentials on import. Snyk