CVE-2021-20186

Publication date 28 January 2021

Last updated 26 August 2025

Ubuntu priority

Cvss 3 Severity Score

Description

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.

Status

Show unmaintained releases

Package	Ubuntu Release	Status
moodle	26.04 LTS resolute	Not in release
	25.10 questing	Not in release
	25.04 plucky	Not in release
	24.10 oracular	Not in release
	24.04 LTS noble	Not in release
	23.10 mantic	Not in release
	23.04 lunar	Not in release
	22.10 kinetic	Not in release
	22.04 LTS jammy	Not in release
	21.10 impish	Not in release
	21.04 hirsute	Not in release
	20.10 groovy	Not in release
	20.04 LTS focal	Not in release
	18.04 LTS bionic	Vulnerable
	16.04 LTS xenial	Ignored end of standard support, was needed
	14.04 LTS trusty	Not in release

Patch details

For informational purposes only. We recommend not to cherry-pick updates. How can I get the fixes?

Package	Patch details
moodle	Upstream: https://git.moodle.org/gw?p=moodle.git;a=commit;h=11e13d1629a960b431c7f0fbc64e504bd32ae01a

Severity score breakdown

CVSS version: CVSS v3.0

Base score 5.4 · Medium

Base metrics

Parameter	Value
Attack vector	Network
Attack complexity	Low
Privileges required	Low
User interaction	Required
Scope	Changed
Confidentiality impact	Low
Integrity impact	Low
Availability impact	None

Scores

Parameter	Value
Base score	5.4 · Medium
Exploitability score	-
Impact score	-

Vector: CVSS:3.1/AV:N/AC:L/PR:L/UI:R/S:C/C:L/I:L/A:N