CVE-2021-20185: Medium severity moodle vulnerability

Published Jan 28, 2021
·
Updated

It was found in Moodle before version 3.10.1, 3.9.4, 3.8.7 and 3.5.16 that messaging did not impose a character limit when sending messages, which could result in client-side (browser) denial of service for users receiving very large messages.

Affected Software

8 affected componentsFixes available
composer/moodle/moodle>=3.10<3.10.1
3.10.1
composer/moodle/moodle>=3.9<3.9.4
3.9.4
composer/moodle/moodle>=3.8<3.8.7
3.8.7
composer/moodle/moodle>=3.5<3.5.16
3.5.16
Moodle moodle>=3.5.0<3.5.16
Moodle moodle>=3.8.0<3.8.7
Moodle moodle>=3.9.0<3.9.4
Moodle moodle=3.10.0

Event History

Jan 28, 2021
CVE Published
via MITRE·07:01 PM
Data Sourced
via MITRE·07:01 PM
DescriptionWeakness
May 24, 2022
Advisory Published
via GitHub·05:40 PM

Frequently Asked Questions

1

What is the severity of CVE-2021-20185?

CVE-2021-20185 has been classified as having a medium severity due to the potential for client-side denial of service.

2

How do I fix CVE-2021-20185?

To remediate CVE-2021-20185, upgrade to Moodle version 3.10.1, 3.9.4, 3.8.7, or 3.5.16.

3

Which versions of Moodle are affected by CVE-2021-20185?

Moodle versions prior to 3.10.1, 3.9.4, 3.8.7, and 3.5.16 are vulnerable to CVE-2021-20185.

4

What type of attack is associated with CVE-2021-20185?

CVE-2021-20185 could lead to a client-side denial of service attack by allowing the sending of excessively large messages.

5

Is user data compromised by CVE-2021-20185?

CVE-2021-20185 does not compromise user data, but it can disrupt service for users receiving large messages.

Contact

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