bintropy

Bintropy

Detect packers on PE/ELF/Mach-O files using entropy.

This tool is an implementation in Python of Bintropy, an analysis tool presented in this paper in the scope of packing detection based on entropy. It implements both modes of operation and an additional one, respectively on the entire binary, per section or per segment. It uses the entropy values mentioned in the paper for deciding whether the binary contains compressed/encrypted bytes.

It relies on lief for abstracting either PE, ELF or Mach-O executables. This tool thus supports these three formats.

$ pip install bintropy

$ bintropy --help

Modes of operation

Use the -m/--mode option.

• 0: full binary (default)
• 1: per section
• 2: per segment

Note that mode 2 will logically give results very similar to mode 0.

$ bintropy binary
<<< boolean >>>

$ bintropy binary --dot-not-decide
<<< highest block entropy, average block entropy >>>

$ bintropy binary --mode [1|2]
<<< boolean >>>

$ bintropy binary -m [1|2] --do-not-decide
<<< highest block entropy, average block entropy >>>

Benchmarking

Use the -b/--benchmark option to get one more value, the processing time in seconds.

$ bintropy binary -b
<<< boolean, processing time >>>

$ bintropy binary -b --do-not-decide
<<< highest block entropy, average block entropy, processing time >>>

Overriding default entropy values

The reference paper uses 6.677 for the average block entropy and 7.199 for the highest block entropy (obtained by analyzing a dataset of PE files and using the first mode of operation). These values can be overriden with the dedicated options.

$ bintropy binary --threshold-average-entropy 5.678 --threshold-highest-entropy 6.789
[...]

Plotting

This tool features plot generation for drawing binary's sections and the entropy within.

$ bintropy binary --plot
<<< boolean >>>

Example of generated figures:

Related Projects

You may also like these:

• Awesome Executable Packing: A curated list of awesome resources related to executable packing.
• Dataset of packed ELF files: Dataset of ELF samples packed with many different packers.
• Dataset of packed PE files: Dataset of PE samples packed with many different packers (fork of this repository).
• Docker Packing Box: Docker image gathering packers and tools for making datasets of packed executables.
• DSFF: Library implementing the DataSet File Format (DSFF).
• PEiD: Python implementation of the well-known Packed Executable iDentifier (PEiD).
• PyPackerDetect: Packing detection tool for PE files (fork of this repository).
• REMINDer: Packing detector using a simple heuristic (inspired from this paper).