Clickjacking with form input data prefilled from a URL parameter

This lab extends the above Basic clickjacking with CSRF token protection lab (above). The goal of the lab is to change the email address of the user by prepopulating a form using a URL parameter and enticing the user to inadvertently click on an “Update email” button.

Reproduction and proof of concept

  1. Log in to the account on the target website.

  2. Create payload:

  • The iframe src URL points to the target website vulnerable page. In this case, the page containing the “Update email” form, and depends on the unique lab-ID.

  • An initial opacity of 0.1 to align the iframe actions and adjust the position values.

  • Initial top and left values of resp 400px and 80px - to align the “Update email” button with the “Test me” decoy action.

    iframe {
        height: 700px;
        opacity: 0.1;
        z-index: 2;
    div {
        position: absolute;
        top: 400px;
        left: 80;
        z-index: 1;
<div>Test me</div>
<iframe src=""></iframe>
  1. Go to the exploit server and paste the payload into the body field of the form.

  2. Click Store and then View exploit. Hover over “Test me” to make sure the cursor changes to a hand indicating that the div element is positioned correctly. If it is not, change the position of the div element by modifying the top and left properties of the style sheet.

  3. Change “Test me” to “Click me”, set opacity to 0.0001, and click Store.


  1. And Deliver exploit to victim


An attacker needs to craft some HTML that frames the account page and fools the user into updating their email address by clicking on a “Click me” decoy. An account with credentials wiener:peter is available.