CVE-2021-36402 Moodle Improper Input Validation vulnerability

Medium 5.3 Published Updated

Insufficient sanitization of user names in Moodle account confirmation emails allows attackers to inject malicious content for phishing.

Exploited in the wild
Not known
Login needed
Not needed
Attackable
Over the internet
Victim action needed
Not needed
Fix
Available

What is CVE-2021-36402?

CVE-2021-36402 is a medium-severity cross-site scripting vulnerability in Moodle Moodle, published on 6 Mar 2023. An attacker can exploit it over the internet without logging in, with no action from the victim.

Official description

In Moodle, Users' names required additional sanitizing in the account confirmation email, to prevent a self-registration phishing risk.

Weakness: CWE-20

Which versions are affected by CVE-2021-36402?

7 open source packages ship an affected version, including moodle/moodle and moodle. It affects 1 product.

PackageAffectedFixed in
moodle/moodle PackagistAll versions3.9.8
moodle/moodle PackagistAll versions3.9.8
moodle/moodle PackagistFrom 3.10.0-beta3.10.5
moodle/moodle PackagistFrom 3.10.0-beta3.10.5
moodle/moodle PackagistFrom 3.11.0-beta3.11.1
moodle/moodle PackagistFrom 3.11.0-beta3.11.1
1 more packages
moodle BitnamiAll versions3.9.8, 3.10.5, 3.11.1

Products include Moodle Moodle.

How do I fix CVE-2021-36402?

Upgrade moodle/moodle to a fixed version for your release line: 3.9.8, 3.10.5 or 3.11.1.

Escape output for the context it lands in and set a strict Content Security Policy. Upgrading the affected component is the real fix. More about Cross-site scripting.

Is CVE-2021-36402 being exploited?

There is no known exploitation of CVE-2021-36402 in the wild and no public exploit code.

All Moodle Moodle vulnerabilities

Sources

Also known as BIT-moodle-2021-36402, GHSA-gv8f-43pg-c5qw, UBUNTU-CVE-2021-36402.

Is CVE-2021-36402 in your software?

Upload an SBOM and sbomify checks it against every vulnerability here, every day.

Check your SBOMs for free