#include #include #include #include #include #include #include "beacon.h" #include "finddotnet.h" #pragma comment(lib, "ntdll.lib") #pragma comment(lib, "User32.lib") #pragma comment(lib, "Shlwapi.lib") //Code from: https://github.com/outflanknl/C2-Tool-Collection/blob/main/BOF/Psx/SOURCE/Psx.c HRESULT BeaconPrintToStreamW(_In_z_ LPCWSTR lpwFormat, ...) { HRESULT hr = S_FALSE; va_list argList; DWORD dwWritten = 0; if (g_lpStream <= (LPSTREAM)1) { hr = OLE32$CreateStreamOnHGlobal(NULL, TRUE, &g_lpStream); if (FAILED(hr)) { return hr; } } if (g_lpwPrintBuffer <= (LPWSTR)1) { g_lpwPrintBuffer = (LPWSTR)MSVCRT$calloc(MAX_STRING, sizeof(WCHAR)); if (g_lpwPrintBuffer == NULL) { hr = E_FAIL; goto CleanUp; } } va_start(argList, lpwFormat); if (!MSVCRT$_vsnwprintf_s(g_lpwPrintBuffer, MAX_STRING, MAX_STRING -1, lpwFormat, argList)) { hr = E_FAIL; goto CleanUp; } if (g_lpStream != NULL) { if (FAILED(hr = g_lpStream->lpVtbl->Write(g_lpStream, g_lpwPrintBuffer, (ULONG)MSVCRT$wcslen(g_lpwPrintBuffer) * sizeof(WCHAR), &dwWritten))) { goto CleanUp; } } hr = S_OK; CleanUp: if (g_lpwPrintBuffer != NULL) { MSVCRT$memset(g_lpwPrintBuffer, 0, MAX_STRING * sizeof(WCHAR)); // Clear print buffer. } va_end(argList); return hr; } //Code from: https://github.com/outflanknl/C2-Tool-Collection/blob/main/BOF/Psx/SOURCE/Psx.c VOID BeaconOutputStreamW() { STATSTG ssStreamData = { 0 }; SIZE_T cbSize = 0; ULONG cbRead = 0; LARGE_INTEGER pos; LPWSTR lpwOutput = NULL; if (FAILED(g_lpStream->lpVtbl->Stat(g_lpStream, &ssStreamData, STATFLAG_NONAME))) { return; } cbSize = ssStreamData.cbSize.LowPart; lpwOutput = KERNEL32$HeapAlloc(KERNEL32$GetProcessHeap(), HEAP_ZERO_MEMORY, cbSize + 1); if (lpwOutput != NULL) { pos.QuadPart = 0; if (FAILED(g_lpStream->lpVtbl->Seek(g_lpStream, pos, STREAM_SEEK_SET, NULL))) { goto CleanUp; } if (FAILED(g_lpStream->lpVtbl->Read(g_lpStream, lpwOutput, (ULONG)cbSize, &cbRead))) { goto CleanUp; } BeaconPrintf(CALLBACK_OUTPUT, "%ls", lpwOutput); } CleanUp: if (g_lpStream != NULL) { g_lpStream->lpVtbl->Release(g_lpStream); g_lpStream = NULL; } if (g_lpwPrintBuffer != NULL) { MSVCRT$free(g_lpwPrintBuffer); g_lpwPrintBuffer = NULL; } if (lpwOutput != NULL) { KERNEL32$HeapFree(KERNEL32$GetProcessHeap(), 0, lpwOutput); } return; } BOOL FindDotNet() { int p = 0; int pid = 0; char psPath[MAX_PATH]; HANDLE currentProc = NULL; UNICODE_STRING sectionName = { 0 }; WCHAR ProcNumber[30]; OBJECT_ATTRIBUTES objectAttributes; BOOL dotNetFound = FALSE; LPCSTR procName; WCHAR WCprocName[256]; NtGetNextProcess_t pNtGetNextProcess = (NtGetNextProcess_t) GetProcAddress(GetModuleHandle("ntdll.dll"), "NtGetNextProcess"); NtOpenSection_t pNtOpenSection = (NtOpenSection_t) GetProcAddress(GetModuleHandle("ntdll.dll"), "NtOpenSection"); if (pNtGetNextProcess == NULL || pNtOpenSection == NULL) { BeaconPrintf(CALLBACK_ERROR, "Error resolving native API calls!\n"); return -1; } WCHAR objPath[] = L"\\BaseNamedObjects\\Cor_Private_IPCBlock_v4_"; sectionName.Buffer = (PWSTR)KERNEL32$HeapAlloc(KERNEL32$GetProcessHeap(), HEAP_ZERO_MEMORY, 500); BeaconPrintToStreamW(L"\nProcess name\t\t\t\t\t\tPID\n"); BeaconPrintToStreamW(L"=====================================================================\n"); while (!pNtGetNextProcess(currentProc, MAXIMUM_ALLOWED, 0, 0, ¤tProc)) { pid = KERNEL32$GetProcessId(currentProc); if (pid == 0) continue; USER32$wsprintfW(ProcNumber, L"%d", pid); MSVCRT$memset(sectionName.Buffer, 0, 500); MSVCRT$memcpy(sectionName.Buffer, objPath, MSVCRT$wcslen(objPath) * 2); // add section name "prefix" KERNEL32$lstrcatW(sectionName.Buffer, ProcNumber); sectionName.Length = MSVCRT$wcslen(sectionName.Buffer) * 2; // finally, adjust the string size sectionName.MaximumLength = sectionName.Length + 1; InitializeObjectAttributes(&objectAttributes, §ionName, OBJ_CASE_INSENSITIVE, NULL, NULL); HANDLE sectionHandle = NULL; NTSTATUS status = pNtOpenSection(§ionHandle, SECTION_QUERY, &objectAttributes); if (NT_SUCCESS(status)) { KERNEL32$CloseHandle(sectionHandle); KERNEL32$K32GetProcessImageFileNameA(currentProc, psPath, MAX_PATH); procName = SHLWAPI$PathFindFileNameA(psPath); KERNEL32$MultiByteToWideChar(CP_ACP, 0, procName, -1, WCprocName, 256); BeaconPrintToStreamW(L"%-60s\t%d\n", WCprocName, pid); dotNetFound = TRUE; } } return dotNetFound; } int go(void) { BOOL res = NULL; res = FindDotNet(); if(!res) { BeaconPrintf(CALLBACK_ERROR, "No .NET process found!"); } else { BeaconOutputStreamW(); } return 0; }