# LMS by LifterLMS – Online Course, Membership & Learning Management System Plugin for WordPress <= 10.2.1 - Authenticated (Instructor's Assistant+) PHP Object Injection via Lesson Clone and Course Import

- **ID:** WPSEC-2026-0476
- **Plugin:** LifterLMS – WP LMS for eLearning, Online Courses, & Quizzes (`lifterlms`), https://wordpress.org/plugins/lifterlms/
- **Affected versions:** all versions before 10.3.0
- **Fixed in:** 10.3.0 (Update to 10.3.0 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 Low, affected versions Low (as of 2026-10-06)
- **Attack surface analysis:** https://attacksurface.wpsec.com/plugin/lifterlms
- **Fix released:** 2026-10-05
- **Published:** 2026-10-06
- **URL:** https://wpsec.com/vuln/WPSEC-2026-0476/

## Description

The LifterLMS plugin for WordPress is vulnerable to PHP Object Injection in all versions up to, and including, 10.2.1 via the custom meta values of cloned and imported courses and lessons, which were deserialized with maybe_unserialize() without restricting allowed classes. This makes it possible for authenticated attackers who can edit a lesson, such as instructors and instructor's assistants, to store a serialized object in a custom field and have it instantiated when the lesson is cloned, and for users with permission to import courses to do the same through an import file. No known POP chain is present in the plugin itself; if a POP chain is present via another plugin or theme, it could allow file deletion, data retrieval, or code execution.

## References

- https://wpsec.com/vuln/WPSEC-2026-0476/
- https://plugins.svn.wordpress.org/lifterlms/tags/10.3.0/
- https://wordpress.org/plugins/lifterlms/

Source: WPSec, https://wpsec.com/vuln/WPSEC-2026-0476/

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.