CVE-2026-57694 Overview
CVE-2026-57694 is an Insecure Direct Object Reference (IDOR) vulnerability in the Themeum Tutor LMS plugin for WordPress. The flaw stems from an Authorization Bypass Through User-Controlled Key weakness [CWE-639]. Authenticated attackers can manipulate object identifiers to access or modify resources belonging to other users. The vulnerability affects all Tutor LMS versions up to and including 3.9.13. Exploitation requires low privileges and no user interaction over the network. Successful attacks compromise the integrity of LMS data such as courses, enrollments, and student records.
Critical Impact
Authenticated users can bypass access controls to modify resources owned by other Tutor LMS accounts, undermining the integrity of course and learner data.
Affected Products
- Themeum Tutor LMS WordPress plugin versions up to and including 3.9.13
- WordPress sites using Tutor LMS for course delivery and management
- Learning platforms exposing authenticated Tutor LMS endpoints to untrusted users
Discovery Timeline
- 2026-07-13 - CVE-2026-57694 published to NVD
- 2026-07-13 - Last updated in NVD database
Technical Details for CVE-2026-57694
Vulnerability Analysis
The vulnerability resides in Tutor LMS request handlers that accept object identifiers from user input without verifying ownership. An attacker with a low-privilege account, such as a subscriber or student, can substitute another user's object identifier in a request. The application processes the request using the attacker-supplied key rather than validating the caller's authorization against the target resource. This produces a horizontal privilege escalation path across tenants of the same WordPress installation. The integrity impact is high because attackers can alter records they do not own, while confidentiality and availability are not directly impacted according to the published CVSS vector. The EPSS estimate places exploitation probability in the lower tier at the time of publication, though IDOR flaws in widely deployed WordPress plugins routinely see opportunistic abuse.
Root Cause
The root cause is missing authorization enforcement on object identifiers passed as request parameters. Tutor LMS trusts the client-supplied key to select the target record instead of cross-checking it against the authenticated user's permissions. This maps directly to [CWE-639] Authorization Bypass Through User-Controlled Key.
Attack Vector
An attacker authenticates to a WordPress site running a vulnerable Tutor LMS version. The attacker issues a crafted HTTP request to a Tutor LMS endpoint, replacing an identifier such as a course, lesson, or enrollment ID with a value belonging to another user. The server executes the requested action against that resource. See the Patchstack Vulnerability Analysis for technical details.
Detection Methods for CVE-2026-57694
Indicators of Compromise
- Unexpected modifications to Tutor LMS courses, lessons, quizzes, or enrollments performed by accounts that do not own those objects
- HTTP requests to Tutor LMS AJAX or REST endpoints where the numeric object identifier does not correlate with the authenticated user's owned resources
- Spikes in admin-ajax.php or /wp-json/tutor/ traffic from low-privilege accounts
Detection Strategies
- Correlate WordPress user IDs from session cookies with the object IDs referenced in Tutor LMS requests, and alert on mismatches
- Audit database change logs on Tutor LMS tables (wp_tutor_*) for updates whose author or user_id field differs from the acting session
- Enable WordPress activity logging plugins to record who edited each course, lesson, or enrollment
Monitoring Recommendations
- Forward WordPress access logs and PHP audit logs to a centralized analytics pipeline for retention and search
- Monitor for enumeration patterns where a single account requests sequential object identifiers
- Track anomalous privilege patterns such as a subscriber account triggering course editing endpoints
How to Mitigate CVE-2026-57694
Immediate Actions Required
- Update Themeum Tutor LMS to a version released after 3.9.13 that contains the vendor fix
- Review Tutor LMS user accounts and remove or downgrade unused low-privilege accounts that could be leveraged for exploitation
- Audit Tutor LMS records created or modified before patching for unauthorized changes
Patch Information
Upgrade Tutor LMS beyond version 3.9.13. Refer to the Patchstack Vulnerability Analysis for the fixed release identifier and vendor advisory links.
Workarounds
- Restrict registration to trusted users and require administrator approval for new accounts on Tutor LMS sites
- Deploy a web application firewall rule to inspect Tutor LMS endpoints and block requests where the referenced object owner does not match the authenticated session
- Temporarily disable Tutor LMS on public-facing sites if patching cannot be applied and untrusted users can register
Disclaimer: This content was generated using AI. While we strive for accuracy, please verify critical information with official sources.
