PE File Entropy Scanner: Detecting Packed & Encrypted Malware

Static malware analysts often triage a suspicious executable before ever running it, and one of the cheapest, most reliable signals is byte-level Shannon entropy: compressed or encrypted data looks statistically like noise, while ordinary code and text do not. This simulator generates a synthetic file's bytes for five realistic profiles — plain text, native PE code, a UPX-style packed binary, a fully encrypted payload, and a realistic "stub + packed body" layout — then slides a real entropy window across the byte stream exactly as tools like PEiD, Detect It Easy and YARA's entropy rule do, rendering the result as a 3D bar landscape that rises into the red zone the moment the data turns high-entropy. Adjust the window size and packing threshold and watch how the same underlying bytes read differently at different scan resolutions.