CVE-2025-31555: ContentMX Content Publisher Auth Bypass

CVE-2025-31555 Overview

CVE-2025-31555 is a missing authorization vulnerability in the ContentMX Content Publisher plugin for WordPress. The flaw affects all versions of contentmx-content-publisher up to and including 1.0.6. Authenticated attackers with low privileges can exploit incorrectly configured access control checks to perform actions restricted to higher-privileged users. The vulnerability is classified under [CWE-862] Missing Authorization and stems from broken access control on plugin functionality. Patchstack cataloged the issue as a broken access control vulnerability affecting WordPress sites running the plugin.

Critical Impact
Authenticated users with minimal privileges can bypass authorization checks to access or modify plugin functionality, resulting in limited integrity and availability impact on affected WordPress sites.

Affected Products

ContentMX Content Publisher WordPress plugin (contentmx-content-publisher)
All versions from initial release through 1.0.6
WordPress installations running the vulnerable plugin

Discovery Timeline

2025-03-31 - CVE-2025-31555 published to NVD
2026-06-17 - Last updated in NVD database

Technical Details for CVE-2025-31555

Vulnerability Analysis

The vulnerability results from missing authorization checks within the ContentMX Content Publisher plugin. WordPress plugins must validate user capabilities before executing privileged actions. This plugin fails to apply proper capability checks on certain functionality exposed to authenticated users. As a result, a low-privileged user such as a subscriber or contributor can invoke plugin actions intended for administrators or editors. The flaw impacts confidentiality minimally but exposes integrity and availability of plugin-managed content.

Root Cause

The root cause is the absence of current_user_can() capability checks or nonce validation on plugin endpoints. WordPress relies on plugin developers to enforce role-based access control at the handler level. When these checks are missing, any authenticated request reaches the underlying business logic. The plugin exposes functionality without verifying whether the requester holds the required role or capability to execute it.

Attack Vector

An attacker requires an authenticated account on the target WordPress site with at least low-level privileges. The attacker sends crafted HTTP requests to the vulnerable plugin endpoints over the network. Because authorization is not enforced, the requests succeed and trigger actions the attacker should not be able to perform. No user interaction from a victim is required. The attack scales trivially against any WordPress site running the vulnerable plugin version.

No verified proof-of-concept code has been published. See the Patchstack Vulnerability Report for technical details.

Detection Methods for CVE-2025-31555

Indicators of Compromise

Unexpected content changes or new posts created by low-privileged accounts on WordPress sites running contentmx-content-publisher.
HTTP requests from subscriber or contributor accounts to admin-ajax.php or plugin-specific endpoints associated with ContentMX Content Publisher.
Unusual plugin configuration changes recorded in the WordPress database without a corresponding administrator session.

Detection Strategies

Audit WordPress access logs for authenticated requests to wp-admin/admin-ajax.php referencing ContentMX plugin actions originating from non-privileged user IDs.
Enumerate installed plugin versions across the estate and flag any instance of contentmx-content-publisher at version 1.0.6 or earlier.
Correlate WordPress user role assignments with recent content publication events to identify privilege mismatches.

Monitoring Recommendations

Enable WordPress audit logging to capture content creation, modification, and plugin setting changes with user attribution.
Monitor for anomalous POST request volumes to plugin endpoints from accounts that historically only perform read operations.
Set alerts on new user registrations followed by rapid access attempts to admin-only plugin functionality.

How to Mitigate CVE-2025-31555

Immediate Actions Required

Inventory all WordPress sites and identify installations of the contentmx-content-publisher plugin at version 1.0.6 or earlier.
Deactivate and remove the plugin on affected sites until a patched version is verified as available.
Restrict new user registration and review existing low-privileged accounts for suspicious activity.

Patch Information

At the time of publication, no fixed version is listed in the available advisory data. Monitor the Patchstack Vulnerability Report and the plugin's WordPress.org listing for a security release addressing the missing authorization flaw.

Workarounds

Uninstall the ContentMX Content Publisher plugin until a patched release is available.
Deploy a web application firewall rule to block requests to plugin endpoints from non-administrator sessions.
Restrict WordPress user registration and enforce least-privilege role assignments to reduce the pool of accounts capable of exploiting the flaw.

bash

# Identify vulnerable plugin installations via WP-CLI
wp plugin list --name=contentmx-content-publisher --fields=name,status,version

# Deactivate and remove the vulnerable plugin
wp plugin deactivate contentmx-content-publisher
wp plugin uninstall contentmx-content-publisher