CVE-2025-32612: User Session Synchronizer CSRF Vulnerability

CVE-2025-32612 Overview

CVE-2025-32612 is a Cross-Site Request Forgery (CSRF) vulnerability in the rafasashi User Session Synchronizer WordPress plugin. The flaw affects all versions up to and including 1.4.0. Attackers can chain the CSRF weakness with a Stored Cross-Site Scripting (XSS) payload to inject persistent malicious script content into the affected WordPress site. Exploitation requires tricking an authenticated administrator into visiting a crafted page, after which the injected script executes against any user who views the affected page.

Critical Impact
Successful exploitation allows attackers to plant persistent JavaScript that runs in the browser context of site visitors and administrators, enabling session theft, account takeover, and further site compromise.

Affected Products

rafasashi User Session Synchronizer plugin for WordPress
All versions from initial release through 1.4.0
WordPress sites running the vulnerable user-session-synchronizer plugin

Discovery Timeline

2025-04-09 - CVE-2025-32612 published to the National Vulnerability Database (NVD)
2026-04-23 - Last updated in NVD database

Technical Details for CVE-2025-32612

Vulnerability Analysis

The vulnerability combines two distinct weaknesses into a single exploitation chain. The plugin lacks valid CSRF protections (such as WordPress nonce verification) on a state-changing request handler. The same handler also fails to sanitize or encode user-controlled input before storing it and rendering it in the browser. Attackers leverage the missing CSRF control to force an authenticated user to submit a request that writes attacker-controlled HTML or JavaScript into persistent storage. Once stored, the payload executes whenever the affected page is loaded, satisfying the definition of Stored XSS.

The attack scope is marked as changed because script executed in the WordPress administrator's browser can act on resources beyond the vulnerable component, including the wider WordPress site, user sessions, and integrated third-party endpoints. User interaction is required because the exploit relies on the victim visiting an attacker-controlled page while authenticated to the target WordPress instance.

Root Cause

The root cause is a missing or insufficient anti-CSRF token check on a privileged plugin action, classified as [CWE-352] Cross-Site Request Forgery. Because the action also writes input back to the page without contextual output encoding, the missing token check escalates into a Stored XSS condition. Both controls are required, and neither is fully enforced in versions up to 1.4.0.

Attack Vector

The attack vector is network-based and requires user interaction. An attacker hosts a malicious page containing a hidden form or fetch request targeting the vulnerable plugin endpoint on the victim's WordPress site. When an authenticated administrator visits the attacker page, their browser automatically transmits session cookies with the forged request. The plugin processes the request, stores the attacker-supplied script payload, and renders it on subsequent page views. Refer to the Patchstack Vulnerability Report for additional technical detail.

Detection Methods for CVE-2025-32612

Indicators of Compromise

Unexpected <script> tags, event handlers, or obfuscated JavaScript in plugin-managed content fields and database tables.
WordPress access logs showing POST requests to user-session-synchronizer endpoints originating from external Referer headers.
New or modified administrator accounts, plugin settings, or scheduled tasks created shortly after suspicious admin browsing activity.

Detection Strategies

Inspect plugin-controlled database rows for stored HTML or JavaScript that should contain only plain text values.
Correlate admin-authenticated state-changing requests with off-site Referer values, which suggest CSRF abuse.
Review browser content security policy (CSP) violation reports for inline script execution on WordPress admin pages.

Monitoring Recommendations

Enable WordPress audit logging to record plugin configuration changes with timestamps and originating IP addresses.
Monitor outbound connections from admin browsers to unfamiliar domains that may receive exfiltrated cookies or tokens.
Alert on any modification to user roles, options tables, or plugin settings outside scheduled maintenance windows.

How to Mitigate CVE-2025-32612

Immediate Actions Required

Identify all WordPress sites running the User Session Synchronizer plugin at version 1.4.0 or earlier.
Deactivate and remove the plugin until a patched release is confirmed available from the maintainer.
Rotate administrator credentials and invalidate active sessions on any site where the plugin was active.
Audit the WordPress database for stored script content injected through the plugin's input handlers.

Patch Information

At the time of publication, the vulnerability affects versions up to and including 1.4.0. No fixed version is referenced in the available advisory data. Administrators should monitor the Patchstack Vulnerability Report and the plugin's repository for an updated release.

Workarounds

Remove or disable the User Session Synchronizer plugin until a vendor patch is published.
Restrict WordPress admin access using IP allowlists, multi-factor authentication, and dedicated administrative browsers.
Deploy a web application firewall (WAF) rule that enforces same-origin Referer checks on plugin endpoints.
Apply a strict Content Security Policy that blocks inline script execution in the WordPress admin interface.

bash

# Configuration example: remove the vulnerable plugin via WP-CLI
wp plugin deactivate user-session-synchronizer
wp plugin delete user-session-synchronizer