The npm package 'envfile-sync' (version 1.0.0) is a malicious typosquatting package branded as 'envsync' that contains hidden native Windows executable code. The JavaScript API is non-functional and serves as a stub, while the actual payload is a 2.9MB undocumented native Windows PE binary loaded and executed via process.dlopen on module import. This native code execution occurs with the privileges of the host process, posing a significant security risk to any Windows user importing this package. The package documentation falsely claims no binaries exist, misleading auditors and users.