#!/usr/bin/env python # Impacket - Collection of Python classes for working with network protocols. # # Copyright (C) 2023 Fortra. All rights reserved. # # This software is provided under a slightly modified version # of the Apache Software License. See the accompanying LICENSE file # for more information. # # Description: # PSEXEC like functionality example using RemComSvc (https://github.com/kavika13/RemCom) # # Author: # beto (@agsolino) # # Reference for: # DCE/RPC and SMB. # import sys import os import re import cmd import logging from threading import Thread, Lock import argparse import random import string import time from six import PY3 from impacket.examples import logger from impacket import version, smb from impacket.smbconnection import SMBConnection from impacket.dcerpc.v5 import transport from impacket.structure import Structure from impacket.examples import remcomsvc, serviceinstall from impacket.examples.utils import parse_target from impacket.krb5.keytab import Keytab CODEC = sys.stdout.encoding class RemComMessage(Structure): structure = ( ('Command','4096s=""'), ('WorkingDir','260s=""'), ('Priority',' 0: try: s.waitNamedPipe(tid,pipe) pipeReady = True except: tries -= 1 time.sleep(2) pass if tries == 0: raise Exception('Pipe not ready, aborting') fid = s.openFile(tid,pipe,accessMask, creationOption = 0x40, fileAttributes = 0x80) return fid def doStuff(self, rpctransport): dce = rpctransport.get_dce_rpc() try: dce.connect() except Exception as e: if logging.getLogger().level == logging.DEBUG: import traceback traceback.print_exc() logging.critical(str(e)) sys.exit(1) global dialect dialect = rpctransport.get_smb_connection().getDialect() try: unInstalled = False s = rpctransport.get_smb_connection() # We don't wanna deal with timeouts from now on. s.setTimeout(100000) if self.__exeFile is None: installService = serviceinstall.ServiceInstall(rpctransport.get_smb_connection(), remcomsvc.RemComSvc(), self.__serviceName, self.__remoteBinaryName) else: try: f = open(self.__exeFile, 'rb') except Exception as e: logging.critical(str(e)) sys.exit(1) installService = serviceinstall.ServiceInstall(rpctransport.get_smb_connection(), f, self.__serviceName, self.__remoteBinaryName) if installService.install() is False: return if self.__exeFile is not None: f.close() # Check if we need to copy a file for execution if self.__copyFile is not None: installService.copy_file(self.__copyFile, installService.getShare(), os.path.basename(self.__copyFile)) # And we change the command to be executed to this filename self.__command = os.path.basename(self.__copyFile) + ' ' + self.__command tid = s.connectTree('IPC$') fid_main = self.openPipe(s,tid,r'\RemCom_communicaton',0x12019f) packet = RemComMessage() pid = os.getpid() packet['Machine'] = ''.join([random.choice(string.ascii_letters) for _ in range(4)]) if self.__path is not None: packet['WorkingDir'] = self.__path packet['Command'] = self.__command packet['ProcessID'] = pid s.writeNamedPipe(tid, fid_main, packet.getData()) # Here we'll store the command we type so we don't print it back ;) # ( I know.. globals are nasty :P ) global LastDataSent LastDataSent = '' # Create the pipes threads stdin_pipe = RemoteStdInPipe(rpctransport, r'\%s%s%d' % (RemComSTDIN, packet['Machine'], packet['ProcessID']), smb.FILE_WRITE_DATA | smb.FILE_APPEND_DATA, installService.getShare()) stdin_pipe.start() stdout_pipe = RemoteStdOutPipe(rpctransport, r'\%s%s%d' % (RemComSTDOUT, packet['Machine'], packet['ProcessID']), smb.FILE_READ_DATA) stdout_pipe.start() stderr_pipe = RemoteStdErrPipe(rpctransport, r'\%s%s%d' % (RemComSTDERR, packet['Machine'], packet['ProcessID']), smb.FILE_READ_DATA) stderr_pipe.start() # And we stay here till the end ans = s.readNamedPipe(tid,fid_main,8) if len(ans): retCode = RemComResponse(ans) logging.info("Process %s finished with ErrorCode: %d, ReturnCode: %d" % ( self.__command, retCode['ErrorCode'], retCode['ReturnCode'])) installService.uninstall() if self.__copyFile is not None: # We copied a file for execution, let's remove it s.deleteFile(installService.getShare(), os.path.basename(self.__copyFile)) unInstalled = True sys.exit(retCode['ErrorCode']) except SystemExit: raise except Exception as e: if logging.getLogger().level == logging.DEBUG: import traceback traceback.print_exc() logging.debug(str(e)) if unInstalled is False: installService.uninstall() if self.__copyFile is not None: s.deleteFile(installService.getShare(), os.path.basename(self.__copyFile)) sys.stdout.flush() sys.exit(1) class Pipes(Thread): def __init__(self, transport, pipe, permissions, share=None): Thread.__init__(self) self.server = 0 self.transport = transport self.credentials = transport.get_credentials() self.tid = 0 self.fid = 0 self.share = share self.port = transport.get_dport() self.pipe = pipe self.permissions = permissions self.daemon = True def connectPipe(self): try: lock.acquire() global dialect #self.server = SMBConnection('*SMBSERVER', self.transport.get_smb_connection().getRemoteHost(), sess_port = self.port, preferredDialect = SMB_DIALECT) self.server = SMBConnection(self.transport.get_smb_connection().getRemoteName(), self.transport.get_smb_connection().getRemoteHost(), sess_port=self.port, preferredDialect=dialect) user, passwd, domain, lm, nt, aesKey, TGT, TGS = self.credentials if self.transport.get_kerberos() is True: self.server.kerberosLogin(user, passwd, domain, lm, nt, aesKey, kdcHost=self.transport.get_kdcHost(), TGT=TGT, TGS=TGS) else: self.server.login(user, passwd, domain, lm, nt) lock.release() self.tid = self.server.connectTree('IPC$') self.server.waitNamedPipe(self.tid, self.pipe) self.fid = self.server.openFile(self.tid,self.pipe,self.permissions, creationOption = 0x40, fileAttributes = 0x80) self.server.setTimeout(1000000) except: if logging.getLogger().level == logging.DEBUG: import traceback traceback.print_exc() logging.error("Something wen't wrong connecting the pipes(%s), try again" % self.__class__) class RemoteStdOutPipe(Pipes): def __init__(self, transport, pipe, permisssions): Pipes.__init__(self, transport, pipe, permisssions) def run(self): self.connectPipe() global LastDataSent if PY3: __stdoutOutputBuffer, __stdoutData = b"", b"" while True: try: stdout_ans = self.server.readFile(self.tid, self.fid, 0, 1024) except: pass else: try: if stdout_ans != LastDataSent: if len(stdout_ans) != 0: # Append new data to the buffer while there is data to read __stdoutOutputBuffer += stdout_ans promptRegex = rb'([a-zA-Z]:[\\\/])((([a-zA-Z0-9 -\.]*)[\\\/]?)+(([a-zA-Z0-9 -\.]+))?)?>$' endsWithPrompt = bool(re.match(promptRegex, __stdoutOutputBuffer) is not None) if endsWithPrompt == True: # All data, we shouldn't have encoding errors # Adding a space after the prompt because it's beautiful __stdoutData = __stdoutOutputBuffer + b" " # Remainder data for next iteration __stdoutOutputBuffer = b"" # print("[+] endsWithPrompt") # print(" | __stdoutData:",__stdoutData) # print(" | __stdoutOutputBuffer:",__stdoutOutputBuffer) elif b'\n' in __stdoutOutputBuffer: # We have read a line, print buffer if it is not empty lines = __stdoutOutputBuffer.split(b"\n") # All lines, we shouldn't have encoding errors __stdoutData = b"\n".join(lines[:-1]) + b"\n" # Remainder data for next iteration __stdoutOutputBuffer = lines[-1] # print("[+] newline in __stdoutOutputBuffer") # print(" | __stdoutData:",__stdoutData) # print(" | __stdoutOutputBuffer:",__stdoutOutputBuffer) if len(__stdoutData) != 0: # There is data to print try: sys.stdout.write(__stdoutData.decode(CODEC)) sys.stdout.flush() __stdoutData = b"" except UnicodeDecodeError: logging.error('Decoding error detected, consider running chcp.com at the target,\nmap the result with ' 'https://docs.python.org/3/library/codecs.html#standard-encodings\nand then execute smbexec.py ' 'again with -codec and the corresponding codec') print(__stdoutData.decode(CODEC, errors='replace')) __stdoutData = b"" else: # Don't echo the command that was sent, and clear it up LastDataSent = b"" # Just in case this got out of sync, i'm cleaning it up if there are more than 10 chars, # it will give false positives tho.. we should find a better way to handle this. # if LastDataSent > 10: # LastDataSent = '' except: pass else: __stdoutOutputBuffer, __stdoutData = "", "" while True: try: stdout_ans = self.server.readFile(self.tid, self.fid, 0, 1024) except: pass else: try: if stdout_ans != LastDataSent: if len(stdout_ans) != 0: # Append new data to the buffer while there is data to read __stdoutOutputBuffer += stdout_ans promptRegex = r'([a-zA-Z]:[\\\/])((([a-zA-Z0-9 -\.]*)[\\\/]?)+(([a-zA-Z0-9 -\.]+))?)?>$' endsWithPrompt = bool(re.match(promptRegex, __stdoutOutputBuffer) is not None) if endsWithPrompt: # All data, we shouldn't have encoding errors # Adding a space after the prompt because it's beautiful __stdoutData = __stdoutOutputBuffer + " " # Remainder data for next iteration __stdoutOutputBuffer = "" elif '\n' in __stdoutOutputBuffer: # We have read a line, print buffer if it is not empty lines = __stdoutOutputBuffer.split("\n") # All lines, we shouldn't have encoding errors __stdoutData = "\n".join(lines[:-1]) + "\n" # Remainder data for next iteration __stdoutOutputBuffer = lines[-1] if len(__stdoutData) != 0: # There is data to print sys.stdout.write(__stdoutData.decode(CODEC)) sys.stdout.flush() __stdoutData = "" else: # Don't echo the command that was sent, and clear it up LastDataSent = "" # Just in case this got out of sync, i'm cleaning it up if there are more than 10 chars, # it will give false positives tho.. we should find a better way to handle this. # if LastDataSent > 10: # LastDataSent = '' except Exception as e: pass class RemoteStdErrPipe(Pipes): def __init__(self, transport, pipe, permisssions): Pipes.__init__(self, transport, pipe, permisssions) def run(self): self.connectPipe() if PY3: __stderrOutputBuffer, __stderrData = b'', b'' while True: try: stderr_ans = self.server.readFile(self.tid, self.fid, 0, 1024) except: pass else: try: if len(stderr_ans) != 0: # Append new data to the buffer while there is data to read __stderrOutputBuffer += stderr_ans if b'\n' in __stderrOutputBuffer: # We have read a line, print buffer if it is not empty lines = __stderrOutputBuffer.split(b"\n") # All lines, we shouldn't have encoding errors __stderrData = b"\n".join(lines[:-1]) + b"\n" # Remainder data for next iteration __stderrOutputBuffer = lines[-1] if len(__stderrData) != 0: # There is data to print try: sys.stdout.write(__stderrData.decode(CODEC)) sys.stdout.flush() __stderrData = b"" except UnicodeDecodeError: logging.error('Decoding error detected, consider running chcp.com at the target,\nmap the result with ' 'https://docs.python.org/3/library/codecs.html#standard-encodings\nand then execute smbexec.py ' 'again with -codec and the corresponding codec') print(__stderrData.decode(CODEC, errors='replace')) __stderrData = b"" else: # Don't echo the command that was sent, and clear it up LastDataSent = b"" # Just in case this got out of sync, i'm cleaning it up if there are more than 10 chars, # it will give false positives tho.. we should find a better way to handle this. # if LastDataSent > 10: # LastDataSent = '' except Exception as e: pass else: __stderrOutputBuffer, __stderrData = '', '' while True: try: stderr_ans = self.server.readFile(self.tid, self.fid, 0, 1024) except: pass else: try: if len(stderr_ans) != 0: # Append new data to the buffer while there is data to read __stderrOutputBuffer += stderr_ans if '\n' in __stderrOutputBuffer: # We have read a line, print buffer if it is not empty lines = __stderrOutputBuffer.split("\n") # All lines, we shouldn't have encoding errors __stderrData = "\n".join(lines[:-1]) + "\n" # Remainder data for next iteration __stderrOutputBuffer = lines[-1] if len(__stderrData) != 0: # There is data to print sys.stdout.write(__stderrData.decode(CODEC)) sys.stdout.flush() __stderrData = "" else: # Don't echo the command that was sent, and clear it up LastDataSent = "" # Just in case this got out of sync, i'm cleaning it up if there are more than 10 chars, # it will give false positives tho.. we should find a better way to handle this. # if LastDataSent > 10: # LastDataSent = '' except: pass class RemoteShell(cmd.Cmd): def __init__(self, server, port, credentials, tid, fid, share, transport): cmd.Cmd.__init__(self, False) self.prompt = '\x08' self.server = server self.transferClient = None self.tid = tid self.fid = fid self.credentials = credentials self.share = share self.port = port self.transport = transport self.intro = '[!] Press help for extra shell commands' def connect_transferClient(self): #self.transferClient = SMBConnection('*SMBSERVER', self.server.getRemoteHost(), sess_port = self.port, preferredDialect = SMB_DIALECT) self.transferClient = SMBConnection('*SMBSERVER', self.server.getRemoteHost(), sess_port=self.port, preferredDialect=dialect) user, passwd, domain, lm, nt, aesKey, TGT, TGS = self.credentials if self.transport.get_kerberos() is True: self.transferClient.kerberosLogin(user, passwd, domain, lm, nt, aesKey, kdcHost=self.transport.get_kdcHost(), TGT=TGT, TGS=TGS) else: self.transferClient.login(user, passwd, domain, lm, nt) def do_help(self, line): print(""" lcd {path} - changes the current local directory to {path} exit - terminates the server process (and this session) lput {src_file, dst_path} - uploads a local file to the dst_path RELATIVE to the connected share (%s) lget {file} - downloads pathname RELATIVE to the connected share (%s) to the current local dir ! {cmd} - executes a local shell cmd """ % (self.share, self.share)) self.send_data('\r\n', False) def do_shell(self, s): os.system(s) self.send_data('\r\n') def do_lget(self, src_path): try: if self.transferClient is None: self.connect_transferClient() import ntpath filename = ntpath.basename(src_path) fh = open(filename,'wb') logging.info("Downloading %s\\%s" % (self.share, src_path)) self.transferClient.getFile(self.share, src_path, fh.write) fh.close() except Exception as e: logging.critical(str(e)) pass self.send_data('\r\n') def do_lput(self, s): try: if self.transferClient is None: self.connect_transferClient() params = s.split(' ') if len(params) > 1: src_path = params[0] dst_path = params[1] elif len(params) == 1: src_path = params[0] dst_path = '/' src_file = os.path.basename(src_path) fh = open(src_path, 'rb') f = dst_path + '/' + src_file pathname = f.replace('/','\\') logging.info("Uploading %s to %s\\%s" % (src_file, self.share, dst_path)) if PY3: self.transferClient.putFile(self.share, pathname, fh.read) else: self.transferClient.putFile(self.share, pathname.decode(sys.stdin.encoding), fh.read) fh.close() except Exception as e: logging.error(str(e)) pass self.send_data('\r\n') def do_lcd(self, s): if s == '': print(os.getcwd()) else: os.chdir(s) self.send_data('\r\n') def emptyline(self): self.send_data('\r\n') return def default(self, line): if PY3: self.send_data(line.encode(CODEC)+b'\r\n') else: self.send_data(line.decode(sys.stdin.encoding).encode(CODEC)+'\r\n') def send_data(self, data, hideOutput = True): if hideOutput is True: global LastDataSent LastDataSent = data else: LastDataSent = '' self.server.writeFile(self.tid, self.fid, data) class RemoteStdInPipe(Pipes): def __init__(self, transport, pipe, permisssions, share=None): self.shell = None Pipes.__init__(self, transport, pipe, permisssions, share) def run(self): self.connectPipe() self.shell = RemoteShell(self.server, self.port, self.credentials, self.tid, self.fid, self.share, self.transport) self.shell.cmdloop() # Process command-line arguments. if __name__ == '__main__': print(version.BANNER) parser = argparse.ArgumentParser(add_help = True, description = "PSEXEC like functionality example using RemComSvc.") parser.add_argument('target', action='store', help='[[domain/]username[:password]@]') parser.add_argument('command', nargs='*', default = ' ', help='command (or arguments if -c is used) to execute at ' 'the target (w/o path) - (default:cmd.exe)') parser.add_argument('-c', action='store',metavar = "pathname", help='copy the filename for later execution, ' 'arguments are passed in the command option') parser.add_argument('-path', action='store', help='path of the command to execute') parser.add_argument('-file', action='store', help="alternative RemCom binary (be sure it doesn't require CRT)") parser.add_argument('-ts', action='store_true', help='adds timestamp to every logging output') parser.add_argument('-debug', action='store_true', help='Turn DEBUG output ON') parser.add_argument('-codec', action='store', help='Sets encoding used (codec) from the target\'s output (default ' '"%s"). If errors are detected, run chcp.com at the target, ' 'map the result with ' 'https://docs.python.org/3/library/codecs.html#standard-encodings and then execute smbexec.py ' 'again with -codec and the corresponding codec ' % CODEC) group = parser.add_argument_group('authentication') group.add_argument('-hashes', action="store", metavar = "LMHASH:NTHASH", help='NTLM hashes, format is LMHASH:NTHASH') group.add_argument('-no-pass', action="store_true", help='don\'t ask for password (useful for -k)') group.add_argument('-k', action="store_true", help='Use Kerberos authentication. Grabs credentials from ccache file ' '(KRB5CCNAME) based on target parameters. If valid credentials cannot be found, it will use the ' 'ones specified in the command line') group.add_argument('-aesKey', action="store", metavar = "hex key", help='AES key to use for Kerberos Authentication ' '(128 or 256 bits)') group.add_argument('-keytab', action="store", help='Read keys for SPN from keytab file') group = parser.add_argument_group('connection') group.add_argument('-dc-ip', action='store', metavar="ip address", help='IP Address of the domain controller. If omitted it will use the domain part (FQDN) specified in ' 'the target parameter') group.add_argument('-target-ip', action='store', metavar="ip address", help='IP Address of the target machine. If omitted it will use whatever was specified as target. ' 'This is useful when target is the NetBIOS name and you cannot resolve it') group.add_argument('-port', choices=['139', '445'], nargs='?', default='445', metavar="destination port", help='Destination port to connect to SMB Server') group.add_argument('-service-name', action='store', metavar="service_name", default = '', help='The name of the service' ' used to trigger the payload') group.add_argument('-remote-binary-name', action='store', metavar="remote_binary_name", default = None, help='This will ' 'be the name of the executable uploaded on the target') if len(sys.argv)==1: parser.print_help() sys.exit(1) options = parser.parse_args() # Init the example's logger theme logger.init(options.ts) if options.codec is not None: CODEC = options.codec else: if CODEC is None: CODEC = 'utf-8' if options.debug is True: logging.getLogger().setLevel(logging.DEBUG) # Print the Library's installation path logging.debug(version.getInstallationPath()) else: logging.getLogger().setLevel(logging.INFO) domain, username, password, remoteName = parse_target(options.target) if domain is None: domain = '' if options.keytab is not None: Keytab.loadKeysFromKeytab (options.keytab, username, domain, options) options.k = True if options.target_ip is None: options.target_ip = remoteName if password == '' and username != '' and options.hashes is None and options.no_pass is False and options.aesKey is None: from getpass import getpass password = getpass("Password:") if options.aesKey is not None: options.k = True command = ' '.join(options.command) if command == ' ': command = 'cmd.exe' executer = PSEXEC(command, options.path, options.file, options.c, int(options.port), username, password, domain, options.hashes, options.aesKey, options.k, options.dc_ip, options.service_name, options.remote_binary_name) executer.run(remoteName, options.target_ip)