CSS & JavaScript Toolbox <= 12.0.6 - Authenticated (Administrator+) Stored Cross-Site Scripting via Assignment Engine Fields
Strategic Overview
- Status
- Patched in 12.0.7
- Affected Plugin
- CSS & JavaScript Toolbox
- Affected Version
<= 12.0.6- CVSS
- 4.4Medium
- Weakness type
- CWE-79 · Improper Neutralization of Input During Web Page Generation ('Cross-site Scripting')
- CVE
CVE-2025-13533
At a glance
CVE-2025-13533 is a medium-severity Improper Neutralization of Input During Web Page Generation ('Cross-site Scripting') vulnerability in the CSS & JavaScript Toolbox WordPress plugin, affecting versions <= 12.0.6. It carries a CVSS score of 4.4 (reachable over the network). Exploitation requires an authenticated account at Administrator level or above. The issue is fixed in version 12.0.7; sites on affected versions should update now. Disclosed September 2026, reported by Kyokito.
Vulnerability Overview
The CSS & JavaScript Toolbox plugin for WordPress is vulnerable to Stored Cross-Site Scripting in all versions up to, and including, 12.0.6 via the Assignment Engine fields. This is due to insufficient input sanitization and output escaping on assignment data fields including Expressions, URLs, and Advanced assignment data. This makes it possible for authenticated attackers, with Administrator-level access and above, to inject arbitrary web scripts in pages that will execute whenever a user accesses the CJT block edit screen in the admin dashboard.
Technical Analysis
The vector marks this flaw as remotely reachable over the network, and no interaction from a victim user.
CWE-79: Improper Neutralization of Input During Web Page Generation ('Cross-site Scripting')
Reaching this weakness in CSS & JavaScript Toolbox <= 12.0.6 takes an account at Administrator level or above. Cross-site scripting happens when input from a request is written into a page without being escaped for the context it lands in, so the browser parses attacker-supplied text as markup or script.
Injected script runs with the privileges of whoever views the affected page, which is how these flaws turn into administrator session theft, silent account creation or persistent backdoors in page content. For CSS & JavaScript Toolbox the fix is 12.0.7: builds <= 12.0.6 are affected, anything from 12.0.7 onward is not.
Remediation
Update to version 12.0.7, or a newer patched version
How does WordSec protect against this?
An attacker needs Administrator access first, so the firewall sees the attempt as traffic from a logged-in account: WordSec's web application firewall inspects request payloads before WordPress loads them. None of that substitutes for the fix: CSS & JavaScript Toolbox 12.0.7 closes this, and updating the plugin is the step that ends it.
- Firewall
- Alerts
External References
Related records
Same weakness class
Other vulnerabilities in CSS & JavaScript Toolbox
Vulnerability data © Defiant, Inc., provided under the Wordfence Intelligence T&C