CVE-2025-4966 Overview
CVE-2025-4966 is a Cross-Site Request Forgery (CSRF) vulnerability affecting the WP Online Users Stats plugin for WordPress in all versions up to and including 1.0.0. The flaw resides in the hk_dataset_results() function, which lacks proper nonce validation. Unauthenticated attackers can craft forged requests that inject malicious web scripts when a site administrator is tricked into clicking a crafted link. Successful exploitation enables script injection in the context of the administrator session, altering site content or facilitating follow-on attacks. The vulnerability is tracked under [CWE-352] and requires user interaction to succeed.
Critical Impact
Attackers can inject malicious scripts into the WordPress admin context by tricking an authenticated administrator into clicking a forged link, leading to potential site compromise.
Affected Products
- hk1993 WP Online Users Stats plugin for WordPress
- All versions up to and including 1.0.0
- WordPress installations with the plugin enabled
Discovery Timeline
- 2025-06-06 - CVE-2025-4966 published to NVD
- 2026-06-17 - Last updated in NVD database
Technical Details for CVE-2025-4966
Vulnerability Analysis
The vulnerability originates in the plugin's hk_dataset_results() administrative handler. The function processes incoming requests without validating a WordPress nonce, which is the standard anti-CSRF token mechanism WordPress provides through wp_verify_nonce() and check_admin_referer(). Because the request handler trusts any authenticated administrator session, an attacker can build an off-site HTML form or URL that submits arbitrary parameters to the plugin endpoint. When an administrator visits the attacker-controlled page, the browser automatically sends the administrator's session cookies with the forged request, and the plugin executes the requested action. The resulting injection can render attacker-supplied script content within the WordPress admin interface. Refer to the WordPress Plugin Code Review for the affected source location.
Root Cause
The root cause is missing nonce validation inside hk_dataset_results(). WordPress plugin developers must call nonce verification before state-changing operations, and this control is absent, allowing forged cross-origin requests to succeed.
Attack Vector
Exploitation requires a network-reachable target and user interaction from a privileged WordPress user. An attacker hosts a crafted page or sends a link containing the malicious request. When the administrator interacts with the link while logged in, the request executes with administrative privileges and injects attacker-controlled script content. See the Wordfence Vulnerability Report for advisory details.
Detection Methods for CVE-2025-4966
Indicators of Compromise
- Unexpected POST or GET requests to plugin admin endpoints containing the hk_dataset_results action originating from external Referer headers
- Presence of unfamiliar <script> tags or encoded payloads within plugin-generated admin views
- Administrator sessions performing dataset actions without a corresponding admin navigation trail in access logs
Detection Strategies
- Inspect web server access logs for cross-origin requests to wp-admin pages that invoke the WP Online Users Stats plugin without a valid _wpnonce parameter
- Enable WordPress audit logging plugins to record administrator-triggered plugin actions and correlate against browsing activity
- Deploy web application firewall rules that flag requests to the plugin handler missing nonce tokens
Monitoring Recommendations
- Monitor for administrator account activity that occurs immediately after clicking external links, especially from webmail or chat clients
- Alert on modifications to plugin data tables or option values outside scheduled maintenance windows
- Review outbound requests from the WordPress host for signs of injected script beaconing to unfamiliar domains
How to Mitigate CVE-2025-4966
Immediate Actions Required
- Deactivate and remove the WP Online Users Stats plugin until a patched release is available
- Restrict access to wp-admin using IP allowlists or an authenticating reverse proxy
- Instruct administrators to log out of WordPress before browsing untrusted content and to use separate browser profiles for admin work
Patch Information
At the time of publication, no vendor patch is referenced in the NVD entry or the WordPress Plugin Developer Page. Administrators should track the plugin repository for an updated release above version 1.0.0 that introduces nonce validation in hk_dataset_results().
Workarounds
- Remove the plugin from production sites where an update is not yet available
- Enforce SameSite=Lax or SameSite=Strict cookies on the WordPress session cookie to reduce cross-site request risk
- Deploy a WAF rule that blocks requests to the vulnerable endpoint when the Referer header is external or the _wpnonce parameter is missing
Disclaimer: This content was generated using AI. While we strive for accuracy, please verify critical information with official sources.
