Smart Custom 404 Error Page <= 11.4.7 - Reflected Cross-Site Scripting
Strategic Overview
- Status
- Patched in 11.4.8
- Affected Plugin
- Smart Custom 404 Error Page
- Affected Version
<= 11.4.7- CVSS
- 6.1Medium
- Weakness type
- CWE-79 · Improper Neutralization of Input During Web Page Generation ('Cross-site Scripting')
- CVE
CVE-2024-9204
At a glance
CVE-2024-9204 is a medium-severity Improper Neutralization of Input During Web Page Generation ('Cross-site Scripting') vulnerability in the Smart Custom 404 Error Page WordPress plugin, affecting versions <= 11.4.7. It carries a CVSS score of 6.1 (reachable over the network; low attack complexity). Exploitation requires no authentication. The issue is fixed in version 11.4.8; sites on affected versions should update now. Disclosed October 2024, reported by Webbernaut.
Vulnerability Overview
The Smart Custom 404 Error Page plugin for WordPress is vulnerable to Reflected Cross-Site Scripting via $_SERVER['REQUEST_URI'] in all versions up to, and including, 11.4.7 due to insufficient input sanitization and output escaping. This makes it possible for unauthenticated attackers to inject arbitrary web scripts in pages that execute if they can successfully trick a user into performing an action such as clicking on a link.
Technical Analysis
The vector marks this flaw as remotely reachable over the network, with low attack complexity — no special timing or configuration is needed, and no privileges on the target site.
CWE-79: Improper Neutralization of Input During Web Page Generation ('Cross-site Scripting')
Smart Custom 404 Error Page <= 11.4.7 carries this weakness at REQUEST_URI, and reaching it takes a caller who can reach the endpoint. 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 Smart Custom 404 Error Page the fix is 11.4.8: builds <= 11.4.7 are affected, anything from 11.4.8 onward is not.
Remediation
Update to version 11.4.8, or a newer patched version
How does WordSec protect against this?
The attempt arrives as an ordinary request to Smart Custom 404 Error Page: WordSec's web application firewall inspects request payloads before WordPress loads them. None of that substitutes for the fix: Smart Custom 404 Error Page 11.4.8 closes this, and updating the plugin is the step that ends it.
- Firewall
- Alerts
External References
Vulnerability data © Defiant, Inc., provided under the Wordfence Intelligence T&C