CVE-2025-7501: Wonder Slider Lite XSS Vulnerability

CVE-2025-7501 Overview

The Wonder Slider Lite plugin for WordPress contains a stored Cross-Site Scripting (XSS) vulnerability affecting all versions up to and including 14.4. The flaw resides in the image title and description Document Object Model (DOM) handling, where the plugin fails to properly sanitize input and escape output. Authenticated users with Contributor-level access or higher can inject arbitrary JavaScript that executes in the browser of any visitor loading the affected page. The issue is tracked under CWE-79, Improper Neutralization of Input During Web Page Generation.

Critical Impact
Authenticated contributors can inject persistent JavaScript that executes against site visitors and administrators, enabling session theft, redirection, and privileged action abuse.

Affected Products

Wonder Slider Lite plugin for WordPress, all versions through 14.4
WordPress sites permitting Contributor-level or higher account registration
Any WordPress installation with the vulnerable plugin activated

Discovery Timeline

2025-07-26 - CVE-2025-7501 published to the National Vulnerability Database
2026-06-17 - Last updated in NVD database

Technical Details for CVE-2025-7501

Vulnerability Analysis

The Wonder Slider Lite plugin renders image metadata—specifically title and description fields—into the slider DOM without applying sufficient input sanitization or output escaping. When a Contributor or higher-privileged user configures a slider, the values supplied for these fields are written back into the rendered HTML with attacker-controlled markup preserved. Because the payload is stored in the WordPress database, it fires on every subsequent page load. The stored nature transforms a single injection into persistent client-side code execution against every visitor of the affected page.

Root Cause

The root cause is missing input sanitization at write time and missing output escaping at render time within the slider engine (wonderpluginslider.js). WordPress provides functions such as wp_kses_post(), sanitize_text_field(), and esc_attr() that must be applied to user-controlled content before it reaches the DOM. The plugin omitted these controls for the image title and description fields, allowing raw HTML and script content to persist and execute.

Attack Vector

The attack path requires an authenticated account with Contributor privileges or above. An attacker with such access edits a slider entry and supplies a crafted payload—for example, an <img> tag with an onerror handler or a <script> block—inside the image title or description field. When any user, including administrators, loads a page or post containing the compromised slider, the injected script executes in their browser session. Consequences include session cookie theft, forced administrative actions via CSRF-like flows, redirection to malicious infrastructure, and drive-by delivery of secondary payloads. Because the scope metric is Changed, the injected script influences resources beyond the plugin's own security boundary.

See the Wordfence Vulnerability Analysis and the WordPress Plugin Change Set for reference details.

Detection Methods for CVE-2025-7501

Indicators of Compromise

Slider records in the WordPress database containing <script>, onerror=, onload=, or javascript: sequences within image title or description fields
Unexpected outbound requests from visitor browsers to attacker-controlled domains after loading pages that embed Wonder Slider Lite content
New or modified sliders authored by Contributor-level accounts that have no legitimate content responsibilities
Administrator sessions exhibiting unauthorized actions shortly after viewing pages containing embedded sliders

Detection Strategies

Query the wp_posts and plugin-specific tables for stored slider metadata and pattern-match on HTML event handlers and script tags
Deploy a Content Security Policy (CSP) in report-only mode to surface inline script violations originating from slider-rendered DOM nodes
Review WordPress audit logs for slider create/update operations performed by non-editorial roles

Monitoring Recommendations

Alert on installation of Wonder Slider Lite versions at or below 14.4 across managed WordPress estates
Monitor for unusual user-agent activity and outbound beacons from browsers rendering CMS pages
Track privilege usage for Contributor accounts, focusing on repeated edits to slider or media-related content types

How to Mitigate CVE-2025-7501

Immediate Actions Required

Update the Wonder Slider Lite plugin to a version later than 14.4 as soon as the vendor publishes a patched release
Audit existing slider entries for injected HTML or JavaScript and remove any suspicious payloads
Review Contributor and higher role assignments; revoke accounts that no longer require access
Rotate administrator session cookies and reset credentials for any account that viewed affected pages

Patch Information

Refer to the WordPress Plugin Change Set and the Wordfence Vulnerability Analysis for remediation status. Apply the fixed release provided by the plugin vendor once available. Verify the version reported in the WordPress plugin dashboard matches the patched build.

Workarounds

Deactivate and remove the Wonder Slider Lite plugin until a patched version is installed
Restrict slider editing to trusted Editor or Administrator accounts through a role management plugin
Deploy a Web Application Firewall (WAF) rule to block HTML and script payloads submitted to slider configuration endpoints
Enforce a strict Content Security Policy that disallows inline script execution site-wide

bash

# Configuration example: enforce a restrictive Content Security Policy in Apache
Header set Content-Security-Policy "default-src 'self'; script-src 'self'; object-src 'none'; base-uri 'self'; frame-ancestors 'self'"