CVE-2021-20186: Moodle

Medium severity, CVSS 5.4. EPSS: 0.8% chance of exploitation in the next 30 days.

It was found in Moodle before version 3.10.1, 3.9.4, 3.8.7 and 3.5.16 that if the TeX notation filter was enabled, additional sanitizing of TeX content was required to prevent the risk of stored XSS.

Affected products

• Moodle Moodle: before 3.5.16 (fixed in 3.5.16); from 3.8.0, before 3.8.7 (fixed in 3.8.7); from 3.9.0, before 3.9.4 (fixed in 3.9.4); from 3.10.0, before 3.10.1 (fixed in 3.10.1)

Published 2021-01-28. Last modified 2026-06-17.