One-Click RCE in ASUS's Preinstalled Driver Software
After ignoring the advice from my friend, I bought a new ASUS motherboard for my PC. I was a little concerned about having a BIOS that would by default silently install software into my OS in the background. But it could be turned off so I figured I would just do that. DriverHub is an interesting piece of driver software because it doesn’t have any GUI. Instead it’s just a background process that communicates with the website driverhub.asus.com and tells you what drivers to install for your system and which ones need updating. Naturally I wanted to know more about how this website knew what drivers my system needed and how it was installing them, so I cracked open the Firefox network tab. As I expected, the website uses RPC to talk to the background process running on my system. This is where the background process hosts an HTTP or Websocket service locally which a website or service can connect to by sending an API request to 127.0.0.1 on a predefined port, in this case 53000. Right about now my elite hacker senses started tingling.
