CVE-2025-39552: Zephyr Project Manager Auth Bypass Flaw

CVE-2025-39552 Overview

CVE-2025-39552 is a Missing Authorization vulnerability [CWE-862] in the Dylan James Zephyr Project Manager plugin for WordPress. The flaw affects all versions up to and including 3.3.200. Authenticated attackers with low privileges can access functionality that should be restricted by access control checks. The vulnerability results from incorrectly configured access control security levels within the plugin's request handlers. Successful exploitation impacts confidentiality and integrity of project management data stored in WordPress installations running the plugin.

Critical Impact
Authenticated users with low privileges can bypass authorization checks and interact with project data or actions intended for higher-privileged roles.

Affected Products

Dylan James Zephyr Project Manager (zephyr-project-manager) WordPress plugin
All versions from initial release through 3.3.200
WordPress sites with the plugin activated and authenticated user registration enabled

Discovery Timeline

2025-04-16 - CVE-2025-39552 published to the National Vulnerability Database (NVD)
2026-06-17 - Last updated in NVD database

Technical Details for CVE-2025-39552

Vulnerability Analysis

The vulnerability stems from missing authorization checks in the Zephyr Project Manager plugin. WordPress plugins commonly expose functionality through AJAX endpoints, REST routes, or admin-post handlers. Each handler must verify both authentication (is_user_logged_in()) and capability (current_user_can()) before executing sensitive actions.

In zephyr-project-manager versions <= 3.3.200, one or more handlers omit or misconfigure these capability checks. Any authenticated user, including low-privilege accounts such as Subscriber, can invoke functionality intended for administrators or project managers. This falls under Broken Access Control [CWE-862].

The issue is classified as a network-exploitable flaw requiring low privileges and no user interaction. The Common Weakness Enumeration (CWE) categorizes this as Missing Authorization, a pattern where the code path relies on obscurity or client-side controls rather than server-side capability validation.

Root Cause

The root cause is the absence of proper current_user_can() capability checks or nonce validation on plugin actions. WordPress developers must enforce authorization on every state-changing endpoint. When these checks are missing, the WordPress role model cannot restrict who executes the action.

Attack Vector

An attacker registers or compromises a low-privileged WordPress account on a site running the vulnerable plugin. The attacker then issues crafted HTTP requests directly to the exposed plugin endpoints. Because the handlers do not enforce role or capability checks, the server processes the requests and returns or modifies project data. Refer to the Patchstack Vulnerability Report for endpoint-level technical details.

Detection Methods for CVE-2025-39552

Indicators of Compromise

Requests to wp-admin/admin-ajax.php with action parameters referencing zephyr or zpm_ from non-administrative user sessions
Unexpected creation, modification, or deletion of projects, tasks, or comments by Subscriber or Contributor accounts
Newly registered low-privilege accounts followed by immediate access to plugin AJAX endpoints
HTTP 200 responses to plugin actions initiated from IP addresses not associated with staff accounts

Detection Strategies

Review WordPress access logs for POST requests to plugin endpoints correlated with low-privilege session cookies
Enable WordPress audit logging plugins to record project data changes and correlate the acting user role against the action performed
Compare plugin database tables against known-good baselines to identify unauthorized modifications

Monitoring Recommendations

Alert on any authenticated request to zephyr-project-manager endpoints from users below the Editor role
Monitor for anomalous request volume against admin-ajax.php targeting plugin-specific actions
Track new user registrations followed by plugin endpoint activity within short time windows

How to Mitigate CVE-2025-39552

Immediate Actions Required

Update the Zephyr Project Manager plugin to a version later than 3.3.200 once released by the vendor
Audit WordPress user accounts and remove unnecessary Subscriber or Contributor accounts
Disable open user registration (Settings > General > Membership) if it is not required for business operations
Review recent project, task, and comment activity for unauthorized changes and restore from backup if tampering is confirmed

Patch Information

At the time of publication, refer to the Patchstack Vulnerability Report for the latest patched version and vendor guidance. Apply the vendor-supplied update through the WordPress plugin management interface as soon as it is available.

Workarounds

Deactivate and remove the zephyr-project-manager plugin until a patched version is installed
Deploy a Web Application Firewall (WAF) rule that blocks unauthenticated and low-privilege requests to plugin AJAX actions
Restrict access to wp-admin paths by IP allowlist where operationally feasible
Enforce the principle of least privilege and audit all custom roles that inherit capabilities beyond their intended scope

bash

# Example WAF rule concept blocking low-privilege access to plugin endpoints
# ModSecurity pseudo-rule
SecRule REQUEST_URI "@contains /wp-admin/admin-ajax.php" \
  "chain,deny,status:403,id:1039552,msg:'Block Zephyr Project Manager plugin actions'"
  SecRule ARGS:action "@rx ^(zpm_|zephyr_)" \
    "chain"
    SecRule REQUEST_COOKIES:/wordpress_logged_in_/ "@rx .+"