add warning when dumping ntds

cme/crackmapexec.py

@@ -302,6 +302,11 @@ def main():
         if ans.lower() not in ['y', 'yes', '']:
             sys.exit(1)
 
+    if (args.ntds and not args.userntds):
+        ans = input(highlight('[!] Dumping the ntds can crash the DC on Windows Server 2019. Use the option --user <user> to dump a specific user safely [Y/n] ', 'red'))
+        if ans.lower() not in ['y', 'yes', '']:
+            sys.exit(1)
+
     try:
         asyncio.run(
             start_threadpool(protocol_object, args, db, targets, jitter)