# Quiz and Survey Master (QSM) – Quiz Maker & Survey Maker <= 11.2.7 - Authenticated (Contributor+) PHP Object Injection via Quiz Settings

- **ID:** WPSEC-2026-0464
- **Plugin:** Quiz and Survey Master (QSM) – Quiz Maker & Survey Maker (`quiz-master-next`), https://wordpress.org/plugins/quiz-master-next/
- **Affected versions:** all versions before 11.2.8
- **Fixed in:** 11.2.8 (Update to 11.2.8 or later.)
- **Severity:** High 7.5 (CVSS:3.1/AV:N/AC:H/PR:L/UI:N/S:U/C:H/I:H/A:H)
- **Weakness:** CWE-502
- **Usage among sites WPSec scans:** plugin Medium, affected versions Medium (as of 2026-10-06)
- **Attack surface analysis:** https://attacksurface.wpsec.com/plugin/quiz-master-next
- **Fix released:** 2026-10-05
- **Published:** 2026-10-06
- **URL:** https://wpsec.com/vuln/WPSEC-2026-0464/

## Description

The Quiz and Survey Master (QSM) plugin for WordPress is vulnerable to PHP Object Injection in all versions up to, and including, 11.2.7 via deserialization of untrusted input in nested quiz setting values, which are passed through maybe_unserialize() when read. This makes it possible for authenticated attackers, with Contributor-level access and above, to inject a PHP object. No POP chain is known to be present in the plugin itself; if a POP chain is present via an additional plugin or theme installed on the target system, it may allow the attacker to delete arbitrary files, retrieve sensitive data, or execute code.

## References

- https://wpsec.com/vuln/WPSEC-2026-0464/
- https://plugins.svn.wordpress.org/quiz-master-next/tags/11.2.8/
- https://wordpress.org/plugins/quiz-master-next/

Source: WPSec, https://wpsec.com/vuln/WPSEC-2026-0464/

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.