MS-OVBA-Crypto

Cryptographic Functions for Office Visual Basic files.

Installation

Use the package manager pip to install MS_OVBA_Compression.

pip install ms_ovba_crypto

Usage

Microsoft VBA files use a custom encryption algorithm to obfuscate visibility and permission fields. The clsid is used as a seed.

import ms_ovba_crypto

data = b'\x00\x00\x00\x00',

clsid = '{9E394C0B-697E-4AEE-9FA6-446F51FB30DC}'
# Random numbers are used in the obfuscation, so the output is not deterministic.
encrypted = ms_ovba_crypto.encrypt(clsid, data)

data = b'\x41\x43\x5A\x5A\x5E\x5A\x5E\x5A\x5E\x5A\x5E'

# returns b'\x00\x00\x00\x00'
ms_ovba_crypto.decrypt(data)

Contributing

Pull requests are welcome. For major changes, please open an issue first to discuss what you would like to change.

Please make sure to update tests as appropriate.

License

MIT