CVE-2026-23799: Tutor LMS Authorization Bypass Vulnerability

CVE-2026-23799 Overview

A Missing Authorization vulnerability has been identified in Themeum Tutor LMS, a popular WordPress learning management system plugin. This vulnerability allows attackers to exploit incorrectly configured access control security levels, potentially enabling unauthorized access to protected functionality and resources within the LMS platform.

Critical Impact

Attackers can bypass authorization controls in Tutor LMS to perform actions without proper permission validation, potentially compromising course content, student data, and administrative functions.

Affected Products

• Themeum Tutor LMS plugin for WordPress versions up to and including 3.9.5

Discovery Timeline

• 2026-03-05 - CVE CVE-2026-23799 published to NVD
• 2026-03-05 - Last updated in NVD database

Technical Details for CVE-2026-23799

Vulnerability Analysis

This vulnerability is classified as CWE-862: Missing Authorization, which occurs when software fails to perform authorization checks when an actor attempts to access a resource or perform an action. In the context of Tutor LMS, this means certain functionality or endpoints lack proper permission validation, allowing unauthorized users to access restricted features.

The broken access control vulnerability in Tutor LMS allows attackers to exploit incorrectly configured access control security levels. This type of flaw typically manifests when application logic assumes authentication is sufficient for authorization, or when permission checks are inconsistently applied across different code paths. WordPress plugins like Tutor LMS often have complex permission structures involving WordPress roles, custom capabilities, and context-specific access rules. When these checks are missing or improperly implemented, users can access functionality intended for higher-privileged accounts.

Root Cause

The root cause stems from missing authorization checks within the Tutor LMS plugin codebase. The plugin fails to properly validate user permissions before allowing access to certain protected functionality. This oversight in the access control implementation allows any authenticated user, or potentially unauthenticated users, to perform actions that should be restricted to administrators, instructors, or other privileged roles within the LMS context.

Attack Vector

The attack vector involves accessing unprotected endpoints or invoking functionality within the Tutor LMS plugin without the required authorization. An attacker would identify endpoints or AJAX handlers that lack proper capability checks, then craft requests to access these resources directly. Since the vulnerability relates to broken access control, exploitation typically requires the attacker to be authenticated to WordPress, though the specific access level required depends on which functionality lacks proper checks.

The vulnerability manifests through missing authorization validation in plugin functionality. For detailed technical analysis, refer to the Patchstack WordPress Vulnerability Report.

Detection Methods for CVE-2026-23799

Indicators of Compromise

• Unexpected changes to course content, enrollments, or user permissions within Tutor LMS
• Unusual API requests or AJAX calls to Tutor LMS endpoints from low-privileged users
• Access log entries showing authenticated users reaching administrative or instructor-only functionality
• Database modifications to Tutor LMS tables that don't correlate with legitimate administrative activity

Detection Strategies

• Monitor WordPress audit logs for unauthorized access attempts to Tutor LMS administrative functions
• Implement web application firewall (WAF) rules to detect and block suspicious request patterns targeting LMS functionality
• Review access logs for patterns indicating privilege escalation attempts or unauthorized resource access
• Deploy SentinelOne Singularity to detect anomalous behavior patterns associated with web application exploitation

Monitoring Recommendations

• Enable detailed logging for all Tutor LMS plugin activity and WordPress user actions
• Configure alerting for administrative actions performed by non-administrator users
• Regularly audit user permissions and role assignments within both WordPress and Tutor LMS
• Monitor for new or modified user accounts with elevated privileges

How to Mitigate CVE-2026-23799

Immediate Actions Required

• Update Themeum Tutor LMS to a version newer than 3.9.5 as soon as a patched version is available
• Review and restrict WordPress user roles to ensure least-privilege access principles are enforced
• Audit recent activity within Tutor LMS for signs of unauthorized access or modifications
• Consider temporarily disabling the Tutor LMS plugin if a patch is not yet available and the risk is unacceptable

Patch Information

Themeum is expected to release a security update addressing this vulnerability. Administrators should monitor the Patchstack vulnerability database and the official Tutor LMS changelog for patch announcements. Update to the latest version immediately once a security fix is released.

Workarounds

• Implement additional access controls at the web server or WAF level to restrict access to sensitive Tutor LMS endpoints
• Limit user registration and enrollment to reduce the potential attack surface
• Review and disable unnecessary Tutor LMS features that may expose additional attack vectors
• Apply WordPress security hardening best practices including limiting login attempts and enforcing strong authentication

# WordPress security hardening example
# Add to wp-config.php to limit user enumeration
define('WP_DEBUG', false);
define('DISALLOW_FILE_EDIT', true);

# Add to .htaccess to restrict admin access by IP (adjust IP ranges as needed)
# <Files wp-login.php>
#   Order Deny,Allow
#   Deny from all
#   Allow from YOUR.IP.ADDRESS
# </Files>