What is CVE-2022-40313?

CVE-2022-40313 is a high-severity vulnerability in Moodle, classified under Cross-site Scripting. CVSS score: 7.1/10. Published 2022-09-30.

How severe is CVE-2022-40313?

High severity. CVSS v3 base score is 7.1 out of 10.

Is CVE-2022-40313 known to be exploited?

1 public proof-of-concept repositories are indexed. Not currently listed in the CISA KEV catalog.

XSS in Moodle

CVE-2022-40313

Recursive rendering of Mustache template helpers containing user input could, in some cases, result in an XSS risk or a page failing to load.

Vulnerability class: XSS (Cross-Site Scripting)

Published 2022-09-30 · last modified 2026-06-17.

CVSS v3 metric

CVSS v3 base score 7.1 (High). Vector: CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:C/C:L/I:L/A:L.

EPSS exploit prediction

EPSS: 0.006 (49.0th percentile), scored 2026-10-02.

Very low probability of exploitation in the next 30 days; routine patching cadence is appropriate. 49th percentile — 49.0% of CVEs in the catalogue have a lower EPSS than this one. How to read EPSS.

EPSS over last 30 days · oldest: 0.006 · newest: 0.006 · change: +0.001

Affected products

Moodle
Fedoraproject Extra Packages For Enterprise Linux — versions 8.0
Fedoraproject Fedora — versions 35, 36
Moodle — versions 4.0 to 4.0.3, 3.11 to 3.11.9, 3.9 to 3.9.16 and earlier unsupported versions

Weakness classification (CWE)

CWE-79 — Cross-site Scripting

Public proof-of-concept exploits

jev770/badmoodle-scan

References

bugzilla.redhat.com/show_bug.cgi (Third Party Advisory, Issue Tracking)
moodle.org/mod/forum/discuss.php (Patch, Vendor Advisory)

Frequently asked questions

What is CVE-2022-40313?: CVE-2022-40313 is a high-severity vulnerability in Moodle, classified under Cross-site Scripting. CVSS score: 7.1/10. Published 2022-09-30.
How severe is CVE-2022-40313?: High severity. CVSS v3 base score is 7.1 out of 10.
Is CVE-2022-40313 known to be exploited?: 1 public proof-of-concept repositories are indexed. Not currently listed in the CISA KEV catalog.