CVE-2026-6965

Tutor LMS <= 3.9.9 - Insecure Direct Object Reference to Authenticated (Instructor+) Arbitrary Post Deletion via 'course' GET Parameter

2026-05-12 17:18
molten bit

Strategic Overview

Status
Patched in 3.9.10
Affected Version
<= 3.9.9
CVSS
5.3Medium
Weakness type
CWE-639 · Authorization Bypass Through User-Controlled Key
CVE
CVE-2026-6965
View all Tutor LMS – eLearning and online course solution vulnerabilities

At a glance

CVE-2026-6965 is a medium-severity Authorization Bypass Through User-Controlled Key vulnerability in the Tutor LMS WordPress plugin, affecting versions <= 3.9.9. It carries a CVSS score of 5.3 (reachable over the network; low attack complexity). Exploitation requires no authentication. The issue is fixed in version 3.9.10; sites on affected versions should update now. Disclosed May 2026, reported by molten bit.

Vulnerability Overview

The Tutor LMS – eLearning and online course solution plugin for WordPress is vulnerable to Insecure Direct Object Reference in versions up to and including 3.9.9. This is due to the `get_course_id_by()` function unconditionally trusting the user-supplied `course` GET parameter as the authoritative course ID for content ownership lookups, which is then consumed by `can_user_manage()`, the plugin's sole authorization gate for instructor-level operations, causing it to evaluate instructor membership against the attacker-controlled course rather than the course that actually owns the target content object. This makes it possible for authenticated attackers, with instructor-level access and above, to perform unauthorized operations on any other instructor's course content, including permanently deleting lessons, assignments, quizzes (with cascading deletion of all student attempt data), topics, announcements, and Q&A threads, as well as creating or modifying lessons, topics, and announcements in victim courses, manipulating student quiz grades, and reading unpublished lesson and quiz content.

Technical Analysis

The vector marks this flaw as remotely reachable over the network, with low attack complexity — no special timing or configuration is needed, and no privileges on the target site, and no interaction from a victim user.

CWE-639: Authorization Bypass Through User-Controlled Key

Tutor LMS <= 3.9.9 carries this weakness at get_course_id_by(), and reaching it takes an account at Instructor level or above. Authorization bypass through a user-controlled key, often called insecure direct object reference, means the application looks up a record by an identifier from the request without checking that the caller owns it.

Changing a number in the request is enough to read or modify other users' records, which on commerce and membership sites means customer data. For Tutor LMS the fix is 3.9.10: builds <= 3.9.9 are affected, anything from 3.9.10 onward is not.

Remediation

Update to version 3.9.10, or a newer patched version

How does WordSec protect against this?

Because it turns on account access, WordSec's login security is the relevant layer: role-based two-factor, captcha and brute-force limits raise the cost of getting the account this needs. None of that substitutes for the fix: Tutor LMS 3.9.10 closes this, and updating the plugin is the step that ends it.

  • Login Security
  • Alerts

External References

Related records

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