CVE-2026-104736: thimpress learnpress – wordpress lms plugin for create and sell online courses Deserialization of Untrusted Data

Vulnerability summary

CVE-2026-104736 is a critical (CVSS 9.8) Deserialization of Untrusted Data vulnerability in thimpress learnpress – wordpress lms plugin for create and sell online courses. EPSS estimates a 0.44% chance of exploitation in the next 30 days, higher than 36.5% of scored vulnerabilities.

Timeline

1. 17-10-2026
   PublishedVulnerability first disclosed.

Description

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.

• CWE-502Deserialization of Untrusted DataThe product deserializes untrusted data without sufficiently ensuring that the resulting data will be valid.