The npm package 'stellarfixer' version 1.0.0 contains malicious code that executes a bundled Windows PE file during installation. This binary is a .NET remote-access trojan that establishes a command-and-control channel, captures keystrokes including credentials, records webcam frames, propagates via USB drives, and employs anti-detection and anti-termination techniques. Installing this package on a Windows system leads to full host compromise and remote attacker control.