CVE-2021-20183

Name: CVE-2021-20183
Creator: NVD / NIST
Published: 2021-01-28T19:15:13.16+00:00
License: https://creativecommons.org/publicdomain/zero/1.0/

MEDIUMCVSS 5.4/10EPSS 0.82%

Last modified Jun 17, 2026

CVE-2021-20183 is a medium-severity vulnerability rated 5.4/10 on the CVSS scale. It was found in Moodle before version 3.10.1 that some search inputs were vulnerable to reflected XSS due to insufficient escaping of search queries.. EPSS estimates a 0.82% chance of exploitation in the next 30 days.

Description

It was found in Moodle before version 3.10.1 that some search inputs were vulnerable to reflected XSS due to insufficient escaping of search queries.

Metrics

CVSS 3.1

5.4/10

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

EPSS Probability

0.82%

52.4th percentile

Probability of exploitation in the next 30 days. Learn more

Weakness Enumeration

CWE-79

Affected Software

Vendor	Product	Versions
Moodle	Moodle	< 3.10.1

References

https://moodle.org/mod/forum/discuss.php?d=417166Patch, Vendor Advisory
https://moodle.org/mod/forum/discuss.php?d=417166Patch, Vendor Advisory

Timeline

Published: Jan 28, 2021
Last Modified: Jun 17, 2026
Status: Modified

Frequently Asked Questions

What is CVE-2021-20183?

It was found in Moodle before version 3.10.1 that some search inputs were vulnerable to reflected XSS due to insufficient escaping of search queries.

How severe is CVE-2021-20183?

CVE-2021-20183 has a CVSS score of 5.4/10 (MEDIUM severity). The EPSS model estimates a 0.82% probability of exploitation in the next 30 days.

How do I fix CVE-2021-20183?

Check the vendor references and advisories linked above for patched versions and mitigation guidance. You can also run a Strix scan to test if your systems are affected.

Are you affected by CVE-2021-20183?

Run a free Strix scan to check your systems for this vulnerability.

Scan your code now

Source: NVD / NIST