Introduction to Reflected XSS into a JavaScript string with angle brackets and double quotes HTML-encoded and single quotes escaped

In XSS into a JavaScript string, Reflected Cross-Site Scripting (XSS) is a web security vulnerability where untrusted user input is not properly sanitized or encoded. An attacker can exploit this vulnerability by HTML-encoding angle brackets and double quotes, and escaping single quotes to bypass input filters. This can lead to malicious scripts being injected into vulnerable webpages, potentially causing unauthorized actions, data theft, or compromised user accounts. To mitigate this vulnerability, web developers should implement input validation and output encoding practices, ensuring user-generated content is properly encoded and preventing script execution. Prioritizing web security, secure coding practices, and regular security assessments can minimize the risk of XSS vulnerabilities in JavaScript strings, protecting web application integrity, user data confidentiality, and ensuring a safe browsing experience for users.

Lab Solutions | Practical Work Time XSS into a JavaScript string

This lab contains a reflected cross-site scripting vulnerability in the search query tracking functionality where angle brackets and double are HTML encoded and single quotes are escaped.

To solve this lab, perform a cross-site scripting attack that breaks out of the JavaScript string and calls the alert function.

Stepwise Solution of the lab:-

After accessing this lab, we first noticed it has “Search” functionality.

Now we will check the functionality via any random word.

Go to Dev Tools/Inspect Element –> Debugger –> Lab ID Tab –> (index).

Here we see just because of using apostrophe, the angle bracket is lagging behind. So now let’s use angel bracket instead of apostrophe.

Well, it’s no longer lagging behind and applicable for using angel bracket. So In this scenario we can use payload such as below this one.

\'-alert(1)//

Now let’s see what will happen after injecting this payload. So click on Search button.

Finally! 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: Stored XSS into onclick event with angle brackets and double quotes HTML-encoded and single quotes and backslash escaped, 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