CVE-2023-3105: LearnDash LMS Auth Bypass Vulnerability

CVE-2023-3105 Overview

The LearnDash LMS plugin for WordPress contains an Insecure Direct Object Reference (IDOR) vulnerability in versions up to and including 4.6.0. This security flaw arises from the plugin providing user-controlled access to objects without proper authorization checks, allowing authenticated attackers to bypass access controls and manipulate system resources. The vulnerability enables attackers with any level of account access to change user passwords, potentially leading to complete administrator account takeover.

Critical Impact

Authenticated attackers can exploit this IDOR vulnerability to change passwords for any user account, including administrators, leading to full site compromise.

Affected Products

• LearnDash LMS plugin for WordPress versions up to and including 4.6.0
• WordPress installations running vulnerable LearnDash plugin versions
• Learning management systems built on the LearnDash platform

Discovery Timeline

• 2023-07-12 - CVE-2023-3105 published to NVD
• 2024-11-21 - Last updated in NVD database

Technical Details for CVE-2023-3105

Vulnerability Analysis

This Insecure Direct Object Reference vulnerability stems from inadequate authorization controls within the LearnDash LMS plugin. The plugin fails to properly validate whether the requesting user has appropriate permissions to access or modify specific user objects. When processing password change requests, the application does not verify that the authenticated user should have access to modify the target account's credentials.

The vulnerability is particularly dangerous because it requires only minimal privileges to exploit. Any authenticated user—regardless of their assigned role or permission level within the WordPress installation—can leverage this flaw to escalate their access. This represents a horizontal and vertical privilege escalation vector, as attackers can target both peer-level accounts and higher-privileged administrator accounts.

Root Cause

The root cause of this vulnerability lies in the plugin's failure to implement proper object-level access control when handling user data modifications. The LearnDash plugin provides endpoints or functionality that accepts user-supplied object identifiers (such as user IDs) without validating that the current session's user has legitimate authorization to perform operations on the referenced object. This breaks the principle of least privilege and creates a direct pathway for unauthorized access.

Attack Vector

The attack vector is network-based and requires low complexity to exploit. An attacker must first obtain any valid user account on the target WordPress installation running the vulnerable LearnDash plugin. Once authenticated, the attacker can manipulate requests to reference other user accounts by modifying object identifiers. By targeting administrator accounts and changing their passwords, the attacker can achieve complete site takeover.

The exploitation process involves intercepting or crafting requests that reference the target user's identifier, then submitting a password change operation. Because the plugin fails to verify that the requesting user should have permission to modify the target account, the password change is processed successfully, granting the attacker access to the compromised account.

Detection Methods for CVE-2023-3105

Indicators of Compromise

• Unexpected password change events for administrator or high-privilege accounts without corresponding legitimate user activity
• Authentication logs showing successful logins from unfamiliar IP addresses immediately following password reset actions
• User accounts reporting unexpected password changes or lockouts
• Audit trails showing password modification requests originating from low-privilege user sessions

Detection Strategies

• Implement WordPress activity logging plugins to track all password change events and correlate with user session privileges
• Monitor authentication logs for patterns indicating account takeover attempts, such as rapid password changes across multiple accounts
• Deploy web application firewall (WAF) rules to detect and alert on suspicious parameter manipulation in LearnDash-related endpoints
• Establish baseline user behavior profiles to identify anomalous access patterns indicative of privilege escalation

Monitoring Recommendations

• Enable comprehensive WordPress audit logging with particular attention to user management actions
• Configure alerting for password changes on administrator and editor-level accounts
• Implement real-time monitoring of plugin-specific endpoints for unauthorized object reference attempts
• Regularly review access logs for patterns consistent with IDOR exploitation attempts

How to Mitigate CVE-2023-3105

Immediate Actions Required

• Update the LearnDash LMS plugin to version 4.6.1 or later immediately
• Audit all user accounts, especially administrator accounts, for unauthorized password changes
• Force password resets for all administrator accounts as a precautionary measure
• Review WordPress activity logs for signs of exploitation during the exposure window

Patch Information

LearnDash has addressed this vulnerability in versions after 4.6.0. Administrators should update to the latest available version through the WordPress admin dashboard or by downloading the updated plugin directly from LearnDash. For detailed release information, refer to the LearnDash Release Notes. Additional vulnerability details are available in the Wordfence Vulnerability Report.

Workarounds

• If immediate patching is not possible, temporarily restrict user registration to prevent new low-privilege accounts from being created
• Implement additional authentication factors (MFA/2FA) for administrator accounts to mitigate the impact of password changes
• Consider temporarily disabling the LearnDash plugin until patching can be completed if the risk is deemed critical
• Apply network-level access controls to limit administrative functionality to trusted IP addresses

# WordPress CLI command to update LearnDash plugin
wp plugin update learndash-core --path=/var/www/html/wordpress

# Force password reset for all administrators
wp user reset-password $(wp user list --role=administrator --field=ID) --path=/var/www/html/wordpress