Awesome
PEAS
PEAS is a Python 2 library and command line application for running commands on an ActiveSync server e.g. Microsoft Exchange. It is based on research into Exchange ActiveSync protocol by Adam Rutherford and David Chismon of MWR.
Prerequisites
python
is Python 2, otherwise usepython2
- Python Requests library
Significant source files
Path | Functionality |
---|---|
peas/__main__.py | The command line application. |
peas/peas.py | The PEAS client class that exclusively defines the interface to PEAS. |
peas/py_activesync_helper.py | The helper functions that control the interface to pyActiveSync. |
peas/pyActiveSync/client | The pyActiveSync EAS command builders and parsers. |
Optional installation
python setup.py install
PEAS application
PEAS can be run without installation from the parent peas
directory (containing this readme). PEAS can also be run with the command peas
after installation.
Running PEAS
python -m peas [options] <server>
Example usage
Check server
python -m peas 10.207.7.100
Check credentials
python -m peas --check -u luke2 -p ChangeMe123 10.207.7.100
Get emails
python -m peas --emails -u luke2 -p ChangeMe123 10.207.7.100
Save emails to directory
python -m peas --emails -O emails -u luke2 -p ChangeMe123 10.207.7.100
List file shares
python -m peas --list-unc='\\fictitious-dc' -u luke2 -p ChangeMe123 10.207.7.100
python -m peas --list-unc='\\fictitious-dc\guestshare' -u luke2 -p ChangeMe123 10.207.7.100
Note: Using an IP address or FQDN instead of a hostname in the UNC path may fail.
View file on file share
python -m peas --dl-unc='\\fictitious-dc\guestshare\fileonguestshare.txt' -u luke2 -p ChangeMe123 10.207.7.100
Save file from file share
python -m peas --dl-unc='\\fictitious-dc\guestshare\fileonguestshare.txt' -o file.txt -u luke2 -p ChangeMe123 10.207.7.100
Command line arguments
Run python -m peas --help
for the latest options.
Options:
-h, --help show this help message and exit
-u USER username
-p PASSWORD password
--smb-user=USER username to use for SMB operations
--smb-pass=PASSWORD password to use for SMB operations
--verify-ssl verify SSL certificates (important)
-o FILENAME output to file
-O PATH output directory (for specific commands only, not
combined with -o)
-F repr,hex,b64,stdout,stderr,file
output formatting and encoding options
--check check if account can be accessed with given password
--emails retrieve emails
--list-unc=UNC_PATH list the files at a given UNC path
--dl-unc=UNC_PATH download the file at a given UNC path
PEAS library
PEAS can be imported as a library.
Example code
import peas
# Create an instance of the PEAS client.
client = peas.Peas()
# Display the documentation for the PEAS client.
help(client)
# Disable certificate verification so self-signed certificates don't cause errors.
client.disable_certificate_verification()
# Set the credentials and server to connect to.
client.set_creds({
'server': '10.207.7.100',
'user': 'luke2',
'password': 'ChangeMe123',
})
# Check the credentials are accepted.
print("Auth result:", client.check_auth())
# Retrieve a file share directory listing.
listing = client.get_unc_listing(r'\\fictitious-dc\guestshare')
print(listing)
# Retrieve emails.
emails = client.extract_emails()
print(emails)
Extending
To extend the functionality of PEAS, there is a four step process:
-
Create a builder and parser for the EAS command if it has not been implemented in
pyActiveSync/client
. Copying an existing source file for another command and then editing it has proved effective. The Microsoft EAS documentation describes the structure of the XML that must be created and parsed from the response. -
Create a helper function in
py_activesync_helper.py
that connects to the EAS server over HTTPS, builds and runs the command to achieve the desired functionality. Again, copying an existing function such asget_unc_listing
can be effective. -
Create a method in the
Peas
class that calls the helper function to achieve the desired functionality. This is where PEAS would decide which backend helper function to call if py-eas-client was also an option. -
Add command line support for the feature to the PEAS application by editing
peas/__main__.py
. A new option should be added that when set, calls the method created in the previous step.
Limitations
PEAS has been tested on Kali 2.0 against Microsoft Exchange Server 2013 and 2016. The domain controller was Windows 2012 and the Exchange server was running on the same machine. Results with other configurations may vary.
py-eas-client support is limited to retrieving emails and causes a dependency on Twisted. It was included when the library was being evaluated but it makes sense to remove it from PEAS now, as all functionality can be provided by pyActiveSync.
The licence may be restrictive due to the inclusion of pyActiveSync, which uses the GPLv2.
The requirement to know the hostname of the target machine for file share access may impede enumeration.