Showing posts with label WiFi. Show all posts
Showing posts with label WiFi. Show all posts

Monday, January 23, 2012

Guide: Bypass Captive Portals

Ever connected to an open WiFi somewhere, like hotels or airports, and you realize that it isn't open after all. Your browser is being redirected to a site which requires payment or some kind of authentication (Captive Portal). In this guide, I'll show you how to bypass these portals and freely surf the web.

The hack is to send traffic through the DNS protocol, disguising your surfing as a harmless DNS request. This guide does not endorce illegal activity.

A client bypassing the Captive Portal using DNS Tunneling

For this to work, you'll need the following:
  1. A Linux machine which will act as a server (A Windows machine is also possible, but not recommended). This server must have internet access and should be the computer which is always on, or better: a server. NOTE! If your server is already running a DNS service, this will not work.
  2. A client computer for testing.
  3. Port UDP 53 forwarded to server. Check Portforward.com for how to do this.
Let's begin..