Signify, a portmanteau of signature and verify, is a Python module that provides validation and inspection of digital code signatures. These types of signatures are used to verify the authenticity and integrity of executable code, providing assurance about who published a piece of software and whether is has been altered since it was signed.
This library is mostly intended for malware analysts and security professionals to allow validation of these signatures outside their normal ecosystem and enable close inspection of the available data.
Currently, this library is only able to verify Windows Authenticode signatures, the specific Microsoft technology that is used in Windows to verify software integrity. Typically, Authenticode signatures are embedded into the file itself, without altering the functionality of the software. However, these signatures can also be provided by external Authenticode catalogs (.cat files), allowing virtually any file to be signed using this technology.
The following file types are supported, with support for other file types being expected:
- PE executables (.exe, .dll and various other Windows executables)
- MSI files (.msi)
- Catalog files (.stl and .cat)
- Any flat file that is signed through a catalog file
This module is compatible with Python 3.9+.
Installation is very simple:
pip install signify
Support for some file types (including MSI) requires:
pip install signify[full]
Documentation is available at http://signify.readthedocs.io/en/latest/ or in the docs/ directory.
Huge thanks to Germano Caronni for writing the original code in the verify_sigs project, on which this project was based.
A multitude of significant improvements and modifications was made on top of their original contribution, including improving PE signature support, adding support for various other files, and moving the original scripts into a modern Python module.