CVE-2025-15027: JAY Login & Register Privilege Escalation

CVE-2025-15027 Overview

CVE-2025-15027 is a critical Privilege Escalation vulnerability affecting the JAY Login & Register plugin for WordPress. The vulnerability exists in all versions up to and including 2.6.03, allowing unauthenticated attackers to elevate their privileges to administrator level by exploiting improper access controls in the user registration functionality.

The flaw stems from the plugin allowing users to update arbitrary user meta through the jay_login_register_ajax_create_final_user function without proper authorization checks. This critical weakness enables complete site takeover by malicious actors who can gain administrative access to vulnerable WordPress installations.

Critical Impact

Unauthenticated attackers can escalate privileges to administrator, leading to complete WordPress site compromise including data theft, malware injection, and full control over site content and functionality.

Affected Products

• JAY Login & Register plugin for WordPress versions up to and including 2.6.03
• WordPress installations with the vulnerable plugin active

Discovery Timeline

• 2026-02-08 - CVE CVE-2025-15027 published to NVD
• 2026-02-09 - Last updated in NVD database

Technical Details for CVE-2025-15027

Vulnerability Analysis

This Privilege Escalation vulnerability is classified under CWE-269 (Improper Privilege Management). The core issue lies in the jay_login_register_ajax_create_final_user function which fails to implement proper authorization checks when processing user meta updates during the registration process.

The vulnerability allows unauthenticated users to manipulate user meta fields that should be restricted, including the wp_capabilities meta key that determines WordPress user roles. By crafting malicious requests to the AJAX handler, attackers can set their newly created account to have administrator-level capabilities.

The attack is network-accessible with low complexity, requiring no user interaction or privileges, making it particularly dangerous for internet-facing WordPress sites running this plugin.

Root Cause

The root cause is inadequate access control validation in the AJAX handler function. The jay_login_register_ajax_create_final_user function processes user meta updates without restricting which meta keys can be modified. This allows attackers to inject privileged role assignments during user creation, bypassing the intended registration workflow that should only create subscriber-level accounts.

The plugin fails to implement a whitelist of allowed meta keys or validate that the requested meta updates are appropriate for the user's intended role level.

Attack Vector

The attack leverages the WordPress AJAX interface to target the vulnerable function. An attacker can send a crafted POST request to the WordPress AJAX endpoint (wp-admin/admin-ajax.php) with the action parameter set to trigger the vulnerable function.

By including specific user meta fields in the request payload, the attacker can assign themselves the administrator role during account creation. This requires no prior authentication, as the AJAX endpoint is accessible to unauthenticated users for registration purposes.

The vulnerability can be exploited in the following sequence:

1. The attacker identifies a WordPress site running the vulnerable JAY Login & Register plugin
2. A crafted AJAX request is sent to the registration endpoint with malicious user meta parameters
3. The vulnerable function processes the request without validating the meta key restrictions
4. A new user account is created with administrator privileges
5. The attacker logs in with the newly created administrator account
6. Full administrative access to the WordPress site is achieved

For additional technical details, refer to the WordPress Plugin Code Reference.

Detection Methods for CVE-2025-15027

Indicators of Compromise

• Unexpected administrator accounts appearing in WordPress user management
• Anomalous AJAX requests to admin-ajax.php with jay_login_register action parameters
• New user registrations with immediate administrator role assignment
• Log entries showing user meta updates to wp_capabilities during registration events

Detection Strategies

• Monitor WordPress user creation events for accounts receiving administrator privileges immediately upon registration
• Implement Web Application Firewall (WAF) rules to detect and block malicious AJAX requests targeting the vulnerable function
• Enable WordPress audit logging to track user role changes and meta updates
• Review access logs for patterns of POST requests to admin-ajax.php containing suspicious payloads

Monitoring Recommendations

• Configure alerts for new administrator account creation
• Monitor plugin-related AJAX endpoint activity for unusual request patterns
• Implement file integrity monitoring on WordPress core and plugin files
• Review user activity logs regularly for unauthorized privilege changes

How to Mitigate CVE-2025-15027

Immediate Actions Required

• Update the JAY Login & Register plugin to a patched version immediately if available
• If no patch is available, deactivate and remove the vulnerable plugin until a fix is released
• Audit existing WordPress user accounts for unauthorized administrator accounts
• Review and remove any suspicious user accounts that may have been created through exploitation
• Implement a WAF rule to block requests to the vulnerable AJAX action

Patch Information

Organizations should check the Wordfence Vulnerability Report for the latest patch information and vendor updates. Ensure that automatic updates are enabled for WordPress plugins or manually update to the latest secure version when available.

Workarounds

• Disable the JAY Login & Register plugin until a security patch is released
• Implement server-level access restrictions to block unauthenticated requests to the vulnerable AJAX endpoint
• Use a security plugin or WAF to monitor and block suspicious user registration attempts
• Restrict user registration functionality if not business-critical until the vulnerability is addressed

# WordPress CLI command to list all administrator users for audit
wp user list --role=administrator --fields=ID,user_login,user_email,user_registered

# Deactivate the vulnerable plugin via WP-CLI
wp plugin deactivate jay-login-register

# Check for recently created users (last 7 days)
wp user list --fields=ID,user_login,user_email,user_registered --format=table | grep "$(date -d '7 days ago' +%Y-%m)"