CVE-2026-18439
The Tutor LMS – eLearning and online course solution plugin for WordPress is vulnerable to Insecure Direct Object Reference in versions up to, and including, 4.0.7 via the tutor_quiz_builder_save AJAX action due to missing validation that nested…
Does this matter?
Lower severity and a low EPSS score (0.43%). Track it; it rarely justifies an emergency change on its own.
Description
The Tutor LMS – eLearning and online course solution plugin for WordPress is vulnerable to Insecure Direct Object Reference in versions up to, and including, 4.0.7 via the tutor_quiz_builder_save AJAX action due to missing validation that nested question_id, answer_id, deleted_question_ids[], and deleted_answer_ids[] values in the submitted payload belong to a quiz/topic/course the requester is authorized to manage. The handler only validates the top-level course_id, topic_id, and (when supplied) payload['ID'], but the nested identifiers are passed straight into $wpdb->update/DELETE statements in QuizBuilder::save_questions(), QuizBuilder::save_question_answers(), and QuizBuilder::handle_delete(). This makes it possible for authenticated attackers, with Instructor-level access and above, to overwrite the content and re-parent arbitrary quiz questions/answers belonging to other instructors or administrators, and to delete arbitrary quiz question and answer rows.
- CVSS 3.1
- 4.3 MEDIUMCVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:N/I:L/A:N
- EPSS
- 0.43% probability · 37th percentile
- Public exploits
- None in Exploit-DB
- CISA KEV
- Not listed
- Weakness
- CWE-639
- Source
- security@wordfence.com
EPSS moved from 0.3% on 22 September 2026 to 0.4% on 26 October 2026.
References
- https://plugins.trac.wordpress.org/browser/tutor/tags/3.9.10/classes/QuizBuilder.php#L156
- https://plugins.trac.wordpress.org/browser/tutor/tags/3.9.10/classes/QuizBuilder.php#L291
- https://plugins.trac.wordpress.org/browser/tutor/tags/3.9.10/classes/QuizBuilder.php#L423
- https://plugins.trac.wordpress.org/browser/tutor/tags/3.9.10/classes/QuizBuilder.php#L430
- https://plugins.trac.wordpress.org/browser/tutor/tags/3.9.10/classes/QuizBuilder.php#L781
- https://plugins.trac.wordpress.org/browser/tutor/tags/4.0.3/classes/QuizBuilder.php#L156
- https://plugins.trac.wordpress.org/browser/tutor/tags/4.0.3/classes/QuizBuilder.php#L291
- https://plugins.trac.wordpress.org/browser/tutor/tags/4.0.3/classes/QuizBuilder.php#L423
- https://plugins.trac.wordpress.org/browser/tutor/tags/4.0.3/classes/QuizBuilder.php#L430
- https://plugins.trac.wordpress.org/browser/tutor/tags/4.0.3/classes/QuizBuilder.php#L781
- https://plugins.trac.wordpress.org/changeset/3690454/tutor/tags/4.0.8/classes/QuizBuilder.php
- https://www.wordfence.com/threat-intel/vulnerabilities/id/6d07c82d-262a-4ac1-9ee5-7ef4d025f66f?source=cve
Source: NVD record, EPSS from FIRST.org, KEV from CISA, exploits from Exploit-DB. Refreshed daily. Download this record as JSON.