#include #include #include "findwebclient.h" #include "beacon.h" //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$memset(g_lpwPrintBuffer, 0, MAX_STRING * sizeof(WCHAR)); } va_end(argList); return hr; } //https://github.com/outflanknl/C2-Tool-Collection/blob/main/BOF/Psx/SOURCE/Psx.c VOID BeaconOutputStreamW() { STATSTG ssStreamData = { 0 }; SIZE_T cbSize = 0; ULONG cbRead = 0; LARGE_INTEGER pos; LPWSTR lpwOutput = NULL; if (FAILED(g_lpStream->lpVtbl->Stat(g_lpStream, &ssStreamData, STATFLAG_NONAME))) { return; } cbSize = ssStreamData.cbSize.LowPart; lpwOutput = KERNEL32$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; } int go(char *args, int len) { char* pipeNameHead = "\\\\"; char* pipeNameTail = "\\pipe\\DAV RPC SERVICE"; BOOL pipeStatus = 0; char* hostname; char* nextHostname; char* debug; int iBytesLen = 0; CHAR *hostFileBytes; WCHAR wHostname[256]; datap parser; BeaconDataParse(&parser, args, len); hostFileBytes = BeaconDataExtract(&parser, &iBytesLen); debug = BeaconDataExtract(&parser, NULL); if(iBytesLen != 0) { BeaconPrintf(CALLBACK_OUTPUT, "[+] Loaded file in memory with a size of %d bytes\n[*] Start WebClient enumeration..\n", iBytesLen); BeaconPrintToStreamW(L"\nEnumeration results:\n"); BeaconPrintToStreamW(L"==============================================\n"); hostname = MSVCRT$strtok(hostFileBytes, "\r\n"); while (hostname != NULL) { nextHostname = MSVCRT$strtok(NULL, "\r\n"); if (nextHostname == NULL) { break; } size_t len = MSVCRT$strlen(hostname); char* fullPipeName = (char*) MSVCRT$malloc(len + MSVCRT$strlen(pipeNameHead) + MSVCRT$strlen(pipeNameTail) + 1); MSVCRT$strcpy(fullPipeName, pipeNameHead); MSVCRT$strcat(fullPipeName, hostname); MSVCRT$strcat(fullPipeName, pipeNameTail); pipeStatus = KERNEL32$WaitNamedPipeA(fullPipeName, 3000); if (pipeStatus == 0 && (MSVCRT$strcmp(debug, "debug") == 0)) { KERNEL32$MultiByteToWideChar(CP_ACP, 0, hostname, -1, wHostname, 256); BeaconPrintToStreamW(L"[-] WebClient service not found on %s\n", wHostname); } else if (pipeStatus == 0) { } else { KERNEL32$MultiByteToWideChar(CP_ACP, 0, hostname, -1, wHostname, 256); BeaconPrintToStreamW(L"[+] WebClient running on %s\n", wHostname); } MSVCRT$free(fullPipeName); hostname = nextHostname; } BeaconOutputStreamW(); } else { BeaconPrintf(CALLBACK_ERROR, "Couldn't load the host file from disk.\n"); } return 0; }