How severe is CVE-2021-36568?

CVE-2021-36568 has a CVSS 3.x base score of 5.4, rated medium severity. It is exploitable over network with low attack complexity, requires low privileges and user interaction. Impact on confidentiality is low, integrity low, and availability none.

Is CVE-2021-36568 being actively exploited?

It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 1% (52nd percentile), an estimate of the probability of exploitation in the next 30 days.

What products are affected by CVE-2021-36568?

CVE-2021-36568 primarily affects Moodle. In total, 5 product configurations (CPEs) are listed as vulnerable; see the affected-products list for the exact versions.

How do I fix CVE-2021-36568?

Review the linked vendor and NVD advisories for patched versions and mitigations, then upgrade or apply the recommended workaround.

When was CVE-2021-36568 published?

CVE-2021-36568 was published on 2022-09-13 and last updated on 2026-06-17.

CVE-2021-36568

CVE-2021-36568 is a medium-severity vulnerability in Moodle with a CVSS 3.x base score of 5.4. It is not currently listed as actively exploited by CISA, and its EPSS exploit-prediction score is low. The underlying weakness is classified as CWE-79.

Key facts

Severity: Medium (CVSS 3.x base score 5.4)
EPSS exploit prediction: 1% (52nd percentile)
Actively exploited: Not listed in CISA KEV
Weakness: CWE-79
Affected product: Moodle
Published: 2022-09-13
Last modified: 2026-06-17

Description

In certain Moodle products after creating a course, it is possible to add in a arbitrary "Topic" a resource, in this case a "Database" with the type "Text" where its values "Field name" and "Field description" are vulnerable to Cross Site Scripting Stored(XSS). This affects Moodle 3.11 and Moodle 3.10.4 and Moodle 3.9.7.

Frequently asked questions

What is CVE-2021-36568?: In certain Moodle products after creating a course, it is possible to add in a arbitrary "Topic" a resource, in this case a "Database" with the type "Text" where its values "Field name" and "Field description" are vulnerable to Cross Site Scripting Stored(XSS). This affects Moodle 3.11 and Moodle 3.10.4 and Moodle 3.9.7.
How severe is CVE-2021-36568?: CVE-2021-36568 has a CVSS 3.x base score of 5.4, rated medium severity. It is exploitable over network with low attack complexity, requires low privileges and user interaction. Impact on confidentiality is low, integrity low, and availability none.
Is CVE-2021-36568 being actively exploited?: It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 1% (52nd percentile), an estimate of the probability of exploitation in the next 30 days.
What products are affected by CVE-2021-36568?: CVE-2021-36568 primarily affects Moodle. In total, 5 product configurations (CPEs) are listed as vulnerable; see the affected-products list for the exact versions.
How do I fix CVE-2021-36568?: Review the linked vendor and NVD advisories for patched versions and mitigations, then upgrade or apply the recommended workaround.
When was CVE-2021-36568 published?: CVE-2021-36568 was published on 2022-09-13 and last updated on 2026-06-17.

References

Affected products (5)

cpe:2.3:a:moodle:moodle:3.9.7:*:*:*:*:*:*:*
cpe:2.3:a:moodle:moodle:3.10.4:*:*:*:*:*:*:*
cpe:2.3:a:moodle:moodle:3.11.0:*:*:*:*:*:*:*
cpe:2.3:o:fedoraproject:fedora:35:*:*:*:*:*:*:*
cpe:2.3:o:fedoraproject:fedora:36:*:*:*:*:*:*:*

More vulnerabilities in Moodle

CVE-2006-4935 — Critical (CVSS 10.0): The Database module in Moodle before 1.6.2 does not properly handle uploaded files, which has unspecified impact and…
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CVE-2004-2236 — Critical (CVSS 10.0): Unknown vulnerability in Moodle before 1.3.3 has unknown impact and attack vectors, related to language setting.
CVE-2004-2237 — Critical (CVSS 10.0): Unknown vulnerability in Moodle before 1.3.4 has unknown impact and attack vectors, related to "strings in Moodle…

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