Deserialization in Thimpress Learnpress – WordPress Lms Plugin For Create And Sell Online Courses

CVE-2026-104736

The LearnPress plugin for WordPress is vulnerable to PHP Object Injection in versions up to, and including, 4.4.10 via deserialization of untrusted input from the 'checkout-email' request parameter during the checkout AJAX action. The value is passed through sanitize_text_field(), which does not strip serialized object syntax, then stored in the LearnPress session table and later fed to LP_Helper::maybe_unserialize() → unserialize() (without an allowed_classes restriction) by LP_Session_Handler::get() on subsequent requests. This makes it possible for unauthenticated attackers to inject a PHP Object.

Vulnerability class: Insecure Deserialization

Published .

CVSS v3 metric

CVSS v3 base score 9.8 (Critical). Vector: CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H.

EPSS exploit prediction

No EPSS score from FIRST.org yet. New CVEs usually get one within a few days; no score means no signal yet, not low risk. How EPSS works.

Affected products

Weakness classification (CWE)

References

Frequently asked questions

What is CVE-2026-104736?
CVE-2026-104736 is a critical-severity vulnerability in Thimpress Learnpress – WordPress Lms Plugin For Create And Sell Online Courses, classified under Deserialization of Untrusted Data. CVSS score: 9.8/10. Published 2026-10-17.
How severe is CVE-2026-104736?
Critical severity. CVSS v3 base score is 9.8 out of 10.