The npm package 'rollup-packages-node-polyfills' is a typosquatting malicious package that executes hidden code upon import. It decodes and runs a base64-encoded command to silently install another malicious package 'cors-update', then dynamically loads and executes code from that package. This behavior is unexpected and unrelated to its advertised functionality as a Rollup Node polyfills plugin. Systems with this package installed should be considered fully compromised, and all secrets and keys on those systems should be rotated immediately.