CVE-2025-49437 Overview
CVE-2025-49437 is a stored Cross-Site Scripting (XSS) vulnerability affecting the WP LOL Rotation WordPress plugin developed by worstguy. The flaw stems from improper neutralization of user-supplied input during web page generation [CWE-79]. Authenticated attackers with low privileges can inject malicious JavaScript payloads that persist within the application and execute in the browsers of other users who view the affected pages. The vulnerability affects all versions of WP LOL Rotation up to and including 1.0. Because the scope changes when the payload executes, a successful attack can affect resources beyond the vulnerable component.
Critical Impact
Authenticated attackers can inject persistent JavaScript payloads that execute against site visitors and administrators, enabling session theft, account takeover, and unauthorized administrative actions.
Affected Products
- WP LOL Rotation plugin for WordPress (league-of-legends-rotation)
- All versions from initial release through 1.0
- WordPress installations that have the plugin activated
Discovery Timeline
- 2025-08-14 - CVE-2025-49437 published to the National Vulnerability Database
- 2026-06-17 - Last updated in NVD database
Technical Details for CVE-2025-49437
Vulnerability Analysis
The WP LOL Rotation plugin fails to properly sanitize and encode user-controlled input before rendering it back into HTML output. This class of flaw, categorized as Improper Neutralization of Input During Web Page Generation, allows attackers to embed arbitrary script content within plugin-managed data. Once stored, the payload executes each time a victim loads an affected page. The vulnerability requires user interaction and low-privilege authentication, which typically maps to a WordPress Contributor or Author role capable of submitting plugin content. Persistence in the database differentiates stored XSS from reflected variants and increases the reliability of exploitation.
Root Cause
The root cause is the absence of adequate output encoding and input validation on fields processed by the plugin. WordPress provides sanitization helpers such as wp_kses(), esc_html(), and esc_attr(), but the vulnerable code paths in WP LOL Rotation 1.0 and earlier do not consistently apply them. Untrusted input flows directly into HTML contexts where the browser interprets it as executable script.
Attack Vector
Exploitation occurs over the network against an authenticated WordPress session with at least low-level privileges. An attacker submits a crafted payload containing JavaScript through an input field the plugin exposes. The payload is stored server-side and later rendered without escaping. When an administrator or another user visits the page containing the stored data, the script executes in their browser session under the site's origin. Consult the Patchstack WordPress Vulnerability Advisory for advisory-specific details on the affected input surface.
Detection Methods for CVE-2025-49437
Indicators of Compromise
- Unexpected <script>, onerror=, onload=, or javascript: fragments stored in WordPress wp_options, wp_postmeta, or plugin-specific tables tied to the league-of-legends-rotation plugin.
- Outbound requests from administrator browsers to unfamiliar domains shortly after loading plugin-managed pages.
- New administrator accounts, unexpected plugin installs, or role changes performed from an administrator's IP after visiting affected pages.
Detection Strategies
- Review plugin database entries for HTML or JavaScript characters that should have been encoded, such as <, >, and quote-wrapped event handlers.
- Enable and monitor WordPress audit logging for content submissions from low-privileged accounts that later render on admin-visible pages.
- Deploy a Content Security Policy (CSP) in report-only mode to surface inline script executions originating from plugin pages.
Monitoring Recommendations
- Alert on browser telemetry showing script execution from WordPress admin sessions that references external hosts.
- Track authentication anomalies for administrator accounts, including session token reuse across geographies.
- Monitor web server access logs for POST requests to plugin endpoints containing encoded script characters such as %3Cscript%3E.
How to Mitigate CVE-2025-49437
Immediate Actions Required
- Deactivate the WP LOL Rotation plugin on all WordPress sites where it is installed until a fixed version is available.
- Audit recently submitted plugin content and remove any entries containing script tags or event handler attributes.
- Rotate credentials and invalidate active sessions for administrator accounts that visited plugin-managed pages.
Patch Information
At the time of publication, no fixed version beyond 1.0 has been indicated in the advisory data. Consult the Patchstack WordPress Vulnerability Advisory for the current patch status and vendor guidance.
Workarounds
- Restrict WordPress role assignments so that only trusted users hold Contributor privileges or higher on affected sites.
- Deploy a Web Application Firewall (WAF) rule to block requests containing common XSS payload patterns targeting the plugin's endpoints.
- Enforce a strict Content Security Policy that disallows inline scripts and limits script sources to known-good origins.
- Remove the plugin entirely if it is not essential to site functionality.
Disclaimer: This content was generated using AI. While we strive for accuracy, please verify critical information with official sources.