MITM Chrome Extension

_readme.md

How to MITM with a chrome extension

• Download these files and update them
• goto chrome://extensions and drag the parent folder holding these files into the window (you may need to turn chrome extension developer mode on)
• goto website and watch the magic.

For some extra awesomeness replace a javascript file with a js file from dropbox with ?dl=1 at the end of the js url. Now you can modify the file locally, it will update itself, and you just have to refresh the browser. Pretty cool!

background.js

chrome.webRequest.onBeforeRequest.addListener(function (details) {
    if (details.url == "https://file you want to replace.js") {
      return {
        redirectUrl: "https://www.replacement file.js"
      };
    }
}, {
    urls: ["https://URL YOU WANT TO MITM/"]
}, ["blocking"]);

manifest.json

{
  "manifest_version": 2,
  "name": "MITM Chrome Ext",
  "description": "",
  "version": "0.1",
  "permissions": [
    "webRequest",
    "webRequestBlocking",
    "https://URL YOU WANT TO MITM/"
  ],
  "background": {"scripts": ["background.js"]}
}

This is awesome!