CVE-2021-39181: Frentix Openolat

High severity, CVSS 8.8. EPSS: 1.9% chance of exploitation in the next 30 days.

OpenOlat is a web-based learning management system (LMS). Prior to version 15.3.18, 15.5.3, and 16.0.0, using a prepared import XML file (e.g. a course) any class on the Java classpath can be instantiated, including spring AOP bean factories. This can be used to execute code arbitrary code by the attacker. The attack requires an OpenOlat user account with the authoring role. It can not be exploited by unregistered users. The problem is fixed in versions 15.3.18, 15.5.3, and 16.0.0. There are no known workarounds aside from upgrading.

Affected products

• Frentix Openolat: before 15.3.18 (fixed in 15.3.18); from 15.5.0, before 15.5.3 (fixed in 15.5.3)

Published 2021-09-01. Last modified 2026-06-17.