CVE-2025-49266: Ultimate Reviews Reflected XSS Vulnerability

CVE-2025-49266 Overview

CVE-2025-49266 is a reflected cross-site scripting (XSS) vulnerability in the Rustaurius Ultimate Reviews plugin for WordPress. The plugin fails to properly neutralize user input during web page generation, allowing attackers to inject arbitrary JavaScript that executes in a victim's browser. The flaw affects all plugin versions up to and including 3.2.14. Exploitation requires user interaction, typically by tricking a target into clicking a crafted link. Successful attacks can lead to session hijacking, credential theft, and unauthorized actions performed in the context of the authenticated WordPress user. The vulnerability is tracked under CWE-79.

Critical Impact
Reflected XSS enables attackers to execute arbitrary JavaScript in administrator browsers, potentially leading to account takeover and full WordPress site compromise.

Affected Products

Rustaurius Ultimate Reviews plugin for WordPress
Versions from n/a through <= 3.2.14
WordPress sites running the vulnerable plugin

Discovery Timeline

2025-06-17 - CVE-2025-49266 published to NVD
2026-04-23 - Last updated in NVD database

Technical Details for CVE-2025-49266

Vulnerability Analysis

The vulnerability stems from improper neutralization of input during web page generation in the Ultimate Reviews plugin. When the plugin reflects user-supplied parameters back into HTML responses, it does not apply adequate output encoding or input sanitization. An attacker crafts a URL containing malicious JavaScript payloads in vulnerable parameters. When a victim follows the link, the server reflects the payload into the response, and the browser executes it within the trust context of the WordPress site.

Because the scope is Changed per the CVSS vector, code injected through the plugin can affect resources beyond the plugin's own security authority, including the broader WordPress administrative interface.

Root Cause

The root cause is missing or insufficient output escaping for request parameters rendered into the page. The plugin treats user-controlled input as trusted HTML rather than escaping it through WordPress functions such as esc_html(), esc_attr(), or wp_kses() before reflecting it into the document.

Attack Vector

Exploitation occurs over the network and requires user interaction. The attacker delivers a crafted URL through phishing, social media, or a malicious site. When the victim, ideally an authenticated administrator, visits the link, the injected script runs in their browser session. The attacker can then exfiltrate session cookies, perform CSRF-like actions, modify content, or pivot to administrative functions. No prior authentication is required to craft the payload, but a victim must trigger the request. Refer to the Patchstack Vulnerability Report for technical details.

Detection Methods for CVE-2025-49266

Indicators of Compromise

Web server access logs containing requests to Ultimate Reviews plugin endpoints with suspicious URL parameters containing <script>, javascript:, or HTML event handlers such as onerror= and onload=.
Outbound requests from administrator browsers to unfamiliar domains shortly after visiting URLs referencing the plugin.
Unexpected administrator session activity, including new user creation or plugin installations following click events on external links.

Detection Strategies

Inspect HTTP request logs for URL-encoded JavaScript payloads targeting Ultimate Reviews query parameters.
Deploy a web application firewall (WAF) ruleset matching reflected XSS patterns on WordPress plugin paths.
Monitor browser-side Content Security Policy (CSP) violation reports for inline script execution attempts.

Monitoring Recommendations

Enable WordPress audit logging to track administrator actions correlated with suspicious request patterns.
Alert on referer headers pointing to untrusted external domains preceding plugin requests.
Review plugin inventory and version data continuously to identify hosts running Ultimate Reviews <= 3.2.14.

How to Mitigate CVE-2025-49266

Immediate Actions Required

Update the Ultimate Reviews plugin to a version above 3.2.14 once the vendor releases a patched release.
Audit WordPress administrator accounts for unauthorized changes performed since the plugin was installed.
Restrict administrative access to trusted networks and require multi-factor authentication for all privileged accounts.

Patch Information

At publication, the vulnerability affects Ultimate Reviews through 3.2.14. Site administrators should consult the Patchstack Vulnerability Report for the current fixed version and apply it through the WordPress plugin manager.

Workarounds

Deactivate and remove the Ultimate Reviews plugin until a patched version is installed.
Deploy a WAF such as Patchstack, Wordfence, or ModSecurity with OWASP CRS rules to block reflected XSS payloads targeting plugin parameters.
Apply a strict Content Security Policy that disallows inline scripts and restricts script sources to trusted origins.
Train administrators to avoid clicking unsolicited links referencing their own WordPress site.

bash

# Example nginx Content Security Policy header to limit inline script execution
add_header Content-Security-Policy "default-src 'self'; script-src 'self'; object-src 'none'; base-uri 'self'; frame-ancestors 'self';" always;