The PyPI package 'data-harvester' version 0.3.1 contains malicious code that, upon import, drops a large base64-encoded Linux ELF executable disguised as a system utility. This executable is saved with open permissions in a hidden directory and a cron job is installed to run it every 12 hours, ensuring persistence. The malicious binary steals cryptocurrency wallet data, encrypts it using embedded RSA code, and exfiltrates it to file-sharing services or IPFS. The package also removes its own metadata and cache directories to erase evidence while maintaining the persistence mechanisms.