# msoffcrypto-tool
[](https://pypi.org/project/msoffcrypto-tool/)
[](https://pypistats.org/packages/msoffcrypto-tool)
[](https://travis-ci.com/nolze/msoffcrypto-tool)
[](https://codecov.io/gh/nolze/msoffcrypto-tool)
[](http://msoffcrypto-tool.readthedocs.io/en/latest/?badge=latest)
msoffcrypto-tool (formerly ms-offcrypto-tool) is Python tool and library for decrypting encrypted MS Office files with password, intermediate key, or private key which generated its escrow key.
## Contents
* [Install](#install)
* [Examples](#examples)
* [Supported encryption methods](#supported-encryption-methods)
* [Tests](#tests)
* [Todo](#todo)
* [Resources](#resources)
* [Use cases and mentions](#use-cases-and-mentions)
* [Contributors](#contributors)
## Install
```
pip install msoffcrypto-tool
```
## Examples
### As CLI tool (with password)
```
msoffcrypto-tool encrypted.docx decrypted.docx -p Passw0rd
```
Password is prompted if you omit the password argument value:
```bash
$ msoffcrypto-tool encrypted.docx decrypted.docx -p
Password:
```
Test if the file is encrypted or not (exit code 0 or 1 is returned):
```
msoffcrypto-tool document.doc --test -v
```
### As library
Password and more key types are supported with library functions.
Basic usage:
```python
import msoffcrypto
encrypted = open("encrypted.docx", "rb")
file = msoffcrypto.OfficeFile(encrypted)
file.load_key(password="Passw0rd") # Use password
with open("decrypted.docx", "wb") as f:
file.decrypt(f)
encrypted.close()
```
Basic usage (in-memory):
```python
import msoffcrypto
import io
import pandas as pd
decrypted = io.BytesIO()
with open("encrypted.xlsx", "rb") as f:
file = msoffcrypto.OfficeFile(f)
file.load_key(password="Passw0rd") # Use password
file.decrypt(decrypted)
df = pd.read_excel(decrypted)
print(df)
```
Advanced usage:
```python
# Verify password before decryption (default: False)
# The ECMA-376 Agile/Standard crypto system allows one to know whether the supplied password is correct before actually decrypting the file
# Currently, the verify_password option is only meaningful for ECMA-376 Agile/Standard Encryption
file.load_key(password="Passw0rd", verify_password=True)
# Use private key
file.load_key(private_key=open("priv.pem", "rb"))
# Use intermediate key (secretKey)
file.load_key(secret_key=binascii.unhexlify("AE8C36E68B4BB9EA46E5544A5FDB6693875B2FDE1507CBC65C8BCF99E25C2562"))
# Check the HMAC of the data payload before decryption (default: False)
# Currently, the verify_integrity option is only meaningful for ECMA-376 Agile Encryption
file.decrypt(open("decrypted.docx", "wb"), verify_integrity=True)
```
## Supported encryption methods
### MS-OFFCRYPTO specs
* [x] ECMA-376 (Agile Encryption/Standard Encryption)
* [x] MS-DOCX (OOXML) (Word 2007-2016)
* [x] MS-XLSX (OOXML) (Excel 2007-2016)
* [x] MS-PPTX (OOXML) (PowerPoint 2007-2016)
* [x] Office Binary Document RC4 CryptoAPI
* [x] MS-DOC (Word 2002, 2003, 2004)
* [x] MS-XLS (Excel 2002, 2003, 2004) (experimental)
* [x] MS-PPT (PowerPoint 2002, 2003, 2004) (partial, experimental)
* [x] Office Binary Document RC4
* [x] MS-DOC (Word 97, 98, 2000)
* [x] MS-XLS (Excel 97, 98, 2000) (experimental)
* [ ] ECMA-376 (Extensible Encryption)
* [ ] XOR Obfuscation
### Other
* [ ] Word 95 Encryption (Word 95 and prior)
* [ ] Excel 95 Encryption (Excel 95 and prior)
* [ ] PowerPoint 95 Encryption (PowerPoint 95 and prior)
PRs are welcome!
## Tests
With [coverage](https://github.com/nedbat/coveragepy) and [pytest](https://pytest.org/):
```
poetry install
poetry run coverage run -m pytest -v
```
## Todo
* [x] Add tests
* [x] Support decryption with passwords
* [x] Support older encryption schemes
* [x] Add function-level tests
* [x] Add API documents
* [x] Publish to PyPI
* [x] Add decryption tests for various file formats
* [x] Integrate with more comprehensive projects handling MS Office files (such as [oletools](https://github.com/decalage2/oletools/)?) if possible
* [x] Add the password prompt mode for CLI
* [x] Improve error types (v4.12.0)
* [ ] Redesign APIs (v5.0.0)
* [ ] Introduce something like `ctypes.Structure`
* [ ] Support encryption
* [ ] Isolate parser
## Resources
* "Backdooring MS Office documents with secret master keys" <http://secuinside.com/archive/2015/2015-1-9.pdf>
* Technical Documents <https://msdn.microsoft.com/en-us/library/cc313105.aspx>
* [MS-OFFCRYPTO] Agile Encryption <https://msdn.microsoft.com/en-us/library/dd949735(v=office.12).aspx>
* LibreOffice/core <https://github.com/LibreOffice/core>
* LibreOffice/mso-dumper <https://github.com/LibreOffice/mso-dumper>
* wvDecrypt <http://www.skynet.ie/~caolan/Packages/wvDecrypt.html>
* Microsoft Office password protection - Wikipedia <https://en.wikipedia.org/wiki/Microsoft_Office_password_protection#History_of_Microsoft_Encryption_password>
* office2john.py <https://github.com/magnumripper/JohnTheRipper/blob/bleeding-jumbo/run/office2john.py>
## Alternatives
* herumi/msoffice <https://github.com/herumi/msoffice>
* DocRecrypt <https://blogs.technet.microsoft.com/office_resource_kit/2013/01/23/now-you-can-reset-or-remove-a-password-from-a-word-excel-or-powerpoint-filewith-office-2013/>
* Apache POI - the Java API for Microsoft Documents <https://poi.apache.org/>
## Use cases and mentions
### General
* <https://repology.org/project/python:msoffcrypto-tool/versions> (kudos to maintainers!)
* <https://checkroth.com/unlocking-password-protected-files.html>
### Malware/maldoc analysis
* <https://github.com/jbremer/sflock/commit/3f6a96abe1dbb4405e4fb7fd0d16863f634b09fb>
* <https://isc.sans.edu/forums/diary/Video+Analyzing+Encrypted+Malicious+Office+Documents/24572/>
### CTF
* <https://github.com/shombo/cyberstakes-writeps-2018/tree/master/word_up>
* <https://github.com/willi123yao/Cyberthon2020_Writeups/blob/master/csit/Lost_Magic>
### In other languages
* <https://github.com/dtjohnson/xlsx-populate>
* <https://github.com/opendocument-app/OpenDocument.core/blob/233663b039/src/internal/ooxml/ooxml_crypto.h>
## Contributors
* <https://github.com/nolze/msoffcrypto-tool/graphs/contributors>