CVE-2025-9703: Ultimate Addons for Elementor XSS Flaw

CVE-2025-9703 Overview

CVE-2025-9703 is a stored Cross-Site Scripting (XSS) vulnerability in the Ultimate Addons for Elementor WordPress plugin, formerly known as Elementor Header & Footer Builder. The flaw affects all versions before 2.5.0. The plugin fails to sanitize the contents of SVG files uploaded through the xmlrpc.php endpoint using base64 encoding. Authenticated attackers with high privileges can upload malicious SVG files containing embedded JavaScript. When a user views the file, the script executes in the victim's browser session under the site's origin.

Critical Impact
Authenticated attackers can upload SVG files containing JavaScript payloads that execute in the browsers of users who view them, enabling session hijacking and content manipulation.

Affected Products

Ultimate Addons for Elementor (formerly Elementor Header & Footer Builder) WordPress plugin
All versions prior to 2.5.0
WordPress sites exposing xmlrpc.php with the plugin installed

Discovery Timeline

2025-10-06 - CVE-2025-9703 published to NVD
2026-06-17 - Last updated in NVD database

Technical Details for CVE-2025-9703

Vulnerability Analysis

The vulnerability is a stored Cross-Site Scripting (XSS) issue rooted in improper input validation of file contents. The plugin accepts SVG uploads via the WordPress xmlrpc.php endpoint using base64-encoded payloads. During upload processing, the plugin decodes the base64 data and stores the SVG file without stripping active content such as <script> tags, event handlers, or <foreignObject> elements.

SVG is an XML-based image format that natively supports embedded JavaScript. When the stored file is rendered in a browser, the embedded script executes within the WordPress site's origin. The attack requires an authenticated account with upload privileges and user interaction to view the uploaded file.

Root Cause

The plugin does not apply SVG sanitization to file contents received through the XML-RPC upload path. While standard admin-ajax upload flows may filter SVG content, the xmlrpc.php code path bypasses this sanitization step. Base64 decoding produces raw XML that reaches the filesystem without being scrubbed through a library such as enshrined/svg-sanitize.

Attack Vector

An attacker with author-level or higher credentials sends an XML-RPC request containing a base64-encoded SVG payload with embedded JavaScript. The plugin decodes and saves the file to the WordPress media library. When an administrator or other user opens or previews the file, the payload executes in their session context, allowing cookie theft, forced administrative actions, or defacement.

See the WPScan Vulnerability Report for additional technical details.

Detection Methods for CVE-2025-9703

Indicators of Compromise

SVG files in the WordPress uploads directory containing <script>, onload, onerror, or <foreignObject> tags
Unexpected POST requests to /xmlrpc.php containing wp.uploadFile method calls with image/svg+xml MIME types
New media library entries with .svg extensions created by non-administrator accounts
Outbound requests from administrator browsers to attacker-controlled domains shortly after viewing media files

Detection Strategies

Scan the wp-content/uploads/ directory for SVG files containing script tags or JavaScript event handlers
Review web server access logs for POST requests to xmlrpc.php with large base64-encoded payloads
Correlate media upload events with the account role and expected user behavior
Deploy Content Security Policy (CSP) violation reporting to catch inline script execution from SVG sources

Monitoring Recommendations

Alert on any successful xmlrpc.php request that results in an SVG file being written to disk
Track authenticated user activity from unusual IP addresses or user agents targeting XML-RPC
Monitor plugin version inventory across WordPress installations to identify hosts running versions below 2.5.0

How to Mitigate CVE-2025-9703

Immediate Actions Required

Update the Ultimate Addons for Elementor plugin to version 2.5.0 or later on all affected WordPress sites
Audit existing SVG files in the media library and remove any containing executable content
Rotate credentials for high-privilege accounts that may have been used to upload malicious files
Review recent XML-RPC activity for signs of exploitation

Patch Information

The vendor addressed the issue in Ultimate Addons for Elementor version 2.5.0 by adding SVG content sanitization to the xmlrpc.php upload handler. Administrators should upgrade through the WordPress plugin dashboard or by manually replacing the plugin directory. Refer to the WPScan Vulnerability Report for advisory details.

Workarounds

Disable xmlrpc.php at the web server level if XML-RPC is not required for site functionality
Restrict SVG uploads by removing image/svg+xml from allowed MIME types in WordPress
Limit upload privileges to trusted administrator accounts only
Deploy a web application firewall rule to block SVG payloads containing <script> tags in XML-RPC requests

bash

# Example: block xmlrpc.php in nginx if XML-RPC is not needed
location = /xmlrpc.php {
    deny all;
    return 403;
}