CVE-2026-25406: Tutor LMS Pro Auth Bypass Vulnerability

CVE-2026-25406 Overview

CVE-2026-25406 is an Authentication Bypass Using an Alternate Path or Channel vulnerability in Themeum Tutor LMS Pro (tutor-pro) that allows Authentication Abuse. This vulnerability affects WordPress installations running the Tutor LMS Pro plugin, enabling attackers to bypass standard authentication mechanisms and gain unauthorized access to protected resources and functionality.

Critical Impact
Attackers with low privileges can exploit this broken authentication vulnerability to bypass security controls, potentially gaining unauthorized access to administrative functions, user data, and course management systems within the WordPress LMS environment.

Affected Products

Tutor LMS Pro versions up to and including 3.9.4
WordPress installations using vulnerable Tutor LMS Pro plugin
Learning Management Systems built on affected Tutor LMS Pro versions

Discovery Timeline

2026-03-25 - CVE-2026-25406 published to NVD
2026-03-26 - Last updated in NVD database

Technical Details for CVE-2026-25406

Vulnerability Analysis

This vulnerability falls under CWE-288 (Authentication Bypass Using an Alternate Path or Channel), which describes a condition where a system that requires authentication can be bypassed by using an alternative authentication path or channel that does not require valid credentials. In the context of Tutor LMS Pro, this broken authentication issue allows attackers to abuse authentication mechanisms to gain unauthorized access.

The vulnerability is particularly concerning for WordPress-based learning management systems as it can potentially allow attackers to access student data, course content, payment information, and administrative functions without proper authorization. Given the network-based attack vector with low complexity requirements, exploitation can occur remotely without user interaction.

Root Cause

The root cause stems from improper implementation of authentication controls within the Tutor LMS Pro plugin. The vulnerability exists due to an alternate authentication path or channel that fails to properly validate user credentials or session tokens before granting access to protected functionality. This authentication abuse vector allows attackers with minimal privileges to escalate their access beyond intended boundaries.

Attack Vector

The attack vector for CVE-2026-25406 is network-based, requiring low attack complexity and low privileges. An attacker can exploit this vulnerability remotely without requiring user interaction. The exploitation path involves:

An attacker identifies an alternate authentication path within the Tutor LMS Pro plugin
The attacker crafts requests that bypass standard authentication checks
By abusing this alternate channel, the attacker gains access to functionality that should require proper authentication
This can result in confidentiality, integrity, and availability impacts to the WordPress LMS installation

The vulnerability mechanism involves authentication bypass through alternate request paths within the plugin's API endpoints or form handlers. For technical details on the specific exploitation method, refer to the Patchstack vulnerability database.

Detection Methods for CVE-2026-25406

Indicators of Compromise

Unusual authentication patterns or login attempts bypassing standard WordPress authentication flows
Unauthorized access to Tutor LMS Pro administrative endpoints or course management functions
Anomalous API requests to tutor-pro plugin endpoints from unauthenticated or low-privilege sessions
Evidence of privilege escalation in WordPress user activity logs

Detection Strategies

Monitor WordPress and Tutor LMS Pro access logs for requests to protected endpoints from unauthorized sessions
Implement Web Application Firewall (WAF) rules to detect and block authentication bypass attempts
Review Tutor LMS Pro plugin activity logs for unauthorized course, user, or payment data access
Deploy endpoint protection solutions to detect post-exploitation behavior on WordPress servers

Monitoring Recommendations

Enable verbose logging for the Tutor LMS Pro plugin and WordPress authentication events
Configure alerts for failed and successful authentication attempts showing unusual patterns
Monitor for unauthorized changes to course content, user roles, or payment settings
Implement real-time security monitoring for WordPress installations running vulnerable plugin versions

How to Mitigate CVE-2026-25406

Immediate Actions Required

Update Tutor LMS Pro to the latest patched version beyond 3.9.4 immediately
Review WordPress user accounts and roles for any unauthorized privilege escalations
Audit recent access logs for signs of exploitation or unauthorized access
Consider temporarily disabling Tutor LMS Pro if an update is not immediately available

Patch Information

Themeum should release a security patch addressing this authentication bypass vulnerability. Administrators should monitor the official Tutor LMS Pro plugin repository and the Patchstack vulnerability database for patch availability and update instructions. Apply the security update as soon as it becomes available.

Workarounds

Implement additional authentication controls at the web server or reverse proxy level
Deploy a Web Application Firewall (WAF) with rules to detect and block authentication bypass attempts
Restrict access to WordPress administrative areas by IP address where feasible
Enable WordPress security plugins with login protection and activity monitoring features
Consider disabling non-essential Tutor LMS Pro features until patched

bash

# WordPress configuration hardening example
# Add to wp-config.php to enhance security monitoring

# Force SSL for admin and logins
define('FORCE_SSL_ADMIN', true);

# Limit login attempts (requires plugin or custom implementation)
# define('WP_LIMIT_LOGIN_ATTEMPTS', true);

# Enable WordPress debug logging for security monitoring
define('WP_DEBUG', true);
define('WP_DEBUG_LOG', true);
define('WP_DEBUG_DISPLAY', false);