CVE-2023-47226 - How an Authenticated (Admin+) Stored XSS in Post Sliders & Post Grids WordPress Plugin (<= 1..20) Can Affect Your Site

In 2023, security researchers found a significant vulnerability in the WordPress plugin "Post Sliders & Post Grids by I Thirteen Web Solution." This vulnerability, assigned CVE-2023-47226, is an Authenticated (Admin+) Stored Cross-Site Scripting (XSS) affecting all plugin versions up to and including 1..20.

In this article, I’ll explain what this vulnerability is, why it matters, provide a technical walk-through, code snippets, exploitation details, and actionable steps for defense. If you’re a site owner or curious about security, this is for you.

What is a Stored XSS?

Let’s make it simple: Stored XSS occurs when an attacker can inject damaging JavaScript code into a site (usually from an input field or form), and that code gets stored in the database. When another user (or even you) visits the affected page, the code runs in their browser. This can steal cookies, deface content, or redirect users.

The big problem with CVE-2023-47226 is *who* can do this. In this case, only someone with an Admin account (or higher) can abuse it. However, if a plugin or theme gives too much privilege to untrusted users, or your site is not tightly locked down, you’re still at risk.

About the Plugin

Post Sliders & Post Grids helps you display blog posts in beautiful sliders or grid layouts. It’s popular for creating homepages or featured content sections.

Versions 1..20 and below are vulnerable!

- Plugin Page
- Official Changelog

Authentication required (Admin+ privileges)

#### Affected File/Function

This XSS vulnerability is found in the plugin’s post grid and slider creation features. When an Admin creates a new Slider or Grid—the plugin fails to sanitize input in certain fields. As a result, JavaScript inserted here is stored in the database, then executed in the browser when the page is visited.

Custom Button Text

- Description/Extra HTML areas

Let’s imagine the plugin’s backend PHP has something like

// BAD: Saving user-supplied input directly!
$title = $_POST['slider_title']; // No sanitization
update_post_meta($post_id, 'slider_title', $title);

// Later, in the admin OR public area:
echo '<h2>' . $title . '</h2>';

If an attacker (with admin access) submits this value in the Slider Title field

<script>alert('XSS!');</script>

Whenever this slider or grid is viewed, the user's browser will execute the code!

Step 1: Log in as an Admin

You must be an administrator (or have plugin access) to add/edit sliders.

When creating or editing a post slider or grid, in the "Title" or any custom field, submit

<img src=x onerror=alert('XSS-CVE-2023-47226')>

or

<script>alert(document.cookie)</script>

Step 3: Trigger the Exploit

Whenever you or another admin/editor visits the slider/grid list or preview, the JavaScript will execute.

Real-World Attack:

A rogue admin could use this to

- Steal other admin/editor cookies

References

- NIST National Vulnerability Database Entry
- Patchstack Advisory

Why Does This Matter? (“If Only Admins Can Use It, Why Worry?”)

1. Privilege Escalation: Some WordPress setups give too many users admin status, or are lax with account security.
2. Plugin & Multisite Scenarios: Other plugins or themes may grant non-trusted users (like contributors) admin rights to this plugin only, opening more risk.
3. Malicious Plugins: If untrusted plugins are installed, they can exploit such flaws to gain persistence or wider access.

Bottom Line:
All code should be sanitized, even admin-facing interfaces.

1. Update the Plugin Right Away

If you’re using Post Sliders & Post Grids v1..20 or older, update immediately to the latest version from the WordPress.org plugin page.

2. Principle of Least Privilege

Don’t give admin rights to users or services that don’t absolutely need it. Review your user list regularly and adjust roles as needed.

3. Install a Web Application Firewall (WAF)

A WAF like Wordfence or Patchstack can help block common XSS payloads, buying time even when a zero-day bug slips in.

4. Run Security Plugins

Keep security plugins updated and run regular scans. Stay aware of new vulnerabilities affecting your stack.

5. Practice Good Hygiene

Review audit trails, logins, and always monitor for changes in plugin settings or unexpected new users.

Conclusion

CVE-2023-47226 shows how even admin-only, “back-end” XSS bugs can present a threat—especially on busy, multi-user WordPress sites. The safest route is always to update plugins and keep strict control over who has admin access.

For hands-on users: always sanitize data and code, no matter where it comes from.

If you want to examine this in your lab or report it responsibly, always get written permission from the site owner first.

Timeline

Published on: 11/08/2023 19:15:00 UTC
Last modified on: 11/14/2023 21:10:00 UTC