CVE-2024-11374: TWChat WordPress Plugin XSS Vulnerability

CVE-2024-11374 Overview

CVE-2024-11374 is a Reflected Cross-Site Scripting (XSS) vulnerability in the TWChat – Send or receive messages from users plugin for WordPress. The flaw affects all versions up to and including 4.0.4. The plugin uses remove_query_arg without properly escaping the returned URL, allowing attacker-controlled input to be reflected into rendered pages. Unauthenticated attackers can inject arbitrary JavaScript that executes in a victim's browser when the victim clicks a crafted link. The issue is tracked under [CWE-79] (Improper Neutralization of Input During Web Page Generation).

Critical Impact
Unauthenticated attackers can execute arbitrary JavaScript in a victim's browser session by tricking them into clicking a specially crafted link, enabling session theft, credential harvesting, and administrative account takeover on affected WordPress sites.

Affected Products

TWChat – Send or receive messages from users plugin for WordPress
All versions up to and including 4.0.4
WordPress sites running the vulnerable plugin build

Discovery Timeline

2024-12-07 - CVE-2024-11374 published to the National Vulnerability Database (NVD)
2026-06-17 - Last updated in NVD database

Technical Details for CVE-2024-11374

Vulnerability Analysis

The vulnerability resides in the plugin's use of the WordPress remove_query_arg() function on user-supplied URL data. The function returns a URL string with a specified query parameter removed, but it does not sanitize or escape the remaining URL components. When the returned value is echoed back into HTML output without passing through esc_url() or esc_attr(), attacker-controlled data breaks out of the intended context.

An attacker crafts a URL containing malicious query parameters or fragments that, when reflected into the page, form valid HTML or JavaScript. The victim must interact with the crafted link for the payload to execute. Because the vulnerability requires no authentication and executes in the victim's browser context, it can target site administrators to escalate impact.

Root Cause

The root cause is missing output encoding around the value returned by remove_query_arg in the plugin's Addon_controller.class.php component. The plugin trusts URL input reflected from $_SERVER['REQUEST_URI'] and writes it back into HTML without contextual escaping, violating WordPress secure coding guidance. See the WordPress Plugin Source Code for the affected code path.

Attack Vector

Exploitation requires network access and user interaction. An attacker distributes a crafted URL pointing to a page on the vulnerable WordPress site with a JavaScript payload embedded in a query parameter. When a logged-in administrator or other user follows the link, the plugin reflects the payload into the response and the browser executes it under the site's origin. The attacker can then steal session cookies, perform actions on behalf of the user, or pivot to plugin and theme modifications. Additional technical detail is available in the Wordfence Vulnerability Intelligence advisory.

No verified proof-of-concept code is publicly available. Refer to the linked Wordfence and WordPress plugin source references for technical details.

Detection Methods for CVE-2024-11374

Indicators of Compromise

Web server access logs containing requests to WordPress pages with suspicious query string values that include <script, javascript:, onerror=, or URL-encoded equivalents such as %3Cscript.
Referer headers pointing to attacker-controlled domains preceding requests to endpoints served by the TWChat plugin.
Unexpected outbound requests from administrator browsers to unknown domains shortly after clicking third-party links.

Detection Strategies

Inventory WordPress installations and identify sites running the TWChat plugin at version 4.0.4 or earlier.
Deploy Web Application Firewall (WAF) rules that block reflected XSS patterns in query strings targeting plugin endpoints.
Review WordPress plugin activity logs for exploitation attempts that pair unusual query parameters with authenticated administrator sessions.

Monitoring Recommendations

Alert on HTTP requests to the site that contain script tags, event handler attributes, or encoded XSS payloads in query parameters.
Monitor administrator account activity for anomalous plugin installs, theme edits, or user creations that could follow a successful XSS-based takeover.
Correlate browser-side security events with server-side access logs to identify successful reflected payload execution.

How to Mitigate CVE-2024-11374

Immediate Actions Required

Update the TWChat plugin to a version later than 4.0.4 once the vendor publishes a patched release.
Deactivate and remove the TWChat plugin from WordPress sites until a fixed version is confirmed available.
Instruct administrators to avoid clicking untrusted links pointing to their own WordPress sites while the plugin remains installed.

Patch Information

No fixed version is referenced in the NVD entry at time of publication. Site owners should monitor the Wordfence Vulnerability Intelligence advisory and the plugin listing on WordPress.org for release information. Apply the vendor patch as soon as it is published and verify the fix escapes URL output produced by remove_query_arg.

Workarounds

Remove or disable the TWChat plugin until a patched version is released.
Deploy WAF signatures that block reflected XSS payloads in query strings targeting the vulnerable plugin endpoints.
Enforce a strict Content Security Policy (CSP) that disallows inline scripts to reduce the impact of reflected XSS.
Require administrators to use dedicated browser profiles when managing WordPress and separate them from general web browsing.

bash

# Example nginx rule to block obvious reflected XSS patterns in query strings
if ($args ~* "(<|%3C)\s*script|javascript:|onerror\s*=") {
    return 403;
}