# Quiz and Survey Master (QSM) <= 11.3.0 - Authenticated (Contributor+) Missing Authorization to Other Authors' Quiz Access and Modification via Abilities API

- **ID:** WPSEC-2026-2894
- **Plugin:** Quiz and Survey Master (QSM) – Quiz Maker & Survey Maker (`quiz-master-next`), https://wordpress.org/plugins/quiz-master-next/
- **Affected versions:** from 11.1.0 before 11.3.1
- **Fixed in:** 11.3.1 (Update to 11.3.1 or later.)
- **Severity:** Medium 5.4 (CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:L/I:L/A:N)
- **Weakness:** CWE-639
- **Usage among sites WPSec scans:** plugin Medium, affected versions Medium (as of 2026-11-12)
- **Attack surface analysis:** https://attacksurface.wpsec.com/plugin/quiz-master-next
- **Fix released:** 2026-11-11
- **Published:** 2026-11-12
- **URL:** https://wpsec.com/vuln/WPSEC-2026-2894/

## Description

The Quiz and Survey Master (QSM) plugin for WordPress is vulnerable to unauthorized access and modification of data via its Abilities API abilities (list-quizzes, get-quiz, list-questions, create-question) in all versions up to, and including, 11.3.0, due to the permission callbacks checking only the generic edit_qsm_quizzes capability rather than ownership of the specific quiz. This makes it possible for authenticated attackers, with Contributor-level access and above, to list and read quizzes and questions belonging to other authors and add questions to them, on sites where the WordPress Abilities API is available.

## References

- https://wpsec.com/vuln/WPSEC-2026-2894/
- https://plugins.svn.wordpress.org/quiz-master-next/tags/11.3.1/
- https://wordpress.org/plugins/quiz-master-next/

Source: WPSec, https://wpsec.com/vuln/WPSEC-2026-2894/

License: CC BY 4.0 (https://creativecommons.org/licenses/by/4.0/). Free to use, share and adapt, also commercially, if you credit WPSec and link to this advisory.