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

- **ID:** WPSEC-2026-0478
- **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-2026-0478/

## 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 field values submitted when lessons are created or cloned through the course builder, which were passed to maybe_unserialize(). This makes it possible for authenticated attackers with access to the course builder for a course, such as instructors and instructor's assistants, to inject a PHP object. No known POP chain is present in the plugin itself; if a POP chain is present via another plugin or theme on the target site, it could allow the attacker to delete arbitrary files, retrieve sensitive data, or execute code.

## References

- https://wpsec.com/vuln/WPSEC-2026-0478/
- https://plugins.svn.wordpress.org/lifterlms/tags/10.3.0/
- https://wordpress.org/plugins/lifterlms/

Source: WPSec, https://wpsec.com/vuln/WPSEC-2026-0478/

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.