The PyPI package 'numpyp' is a malicious typo-squatting package mimicking the popular 'numpy' library. It exports functions that send any input data provided by the user to a hardcoded external server controlled by the attacker without disclosure. This can lead to inadvertent leakage of sensitive information such as secrets or proprietary data if a developer mistakenly installs and uses 'numpyp' instead of 'numpy'.