CVE-2019-18210 — moodle
MEDIUMCVE-2019-18210 is a medium-severity (CVSS 5.4) Cross-site Scripting (XSS) vulnerability in moodle/moodle. The records list no fixed version yet; check the vendor advisory below and apply the mitigations in the meantime.
Moodle Persistent Cross-site Scripting (XSS)
EPSS Exploitation Probability
Probability of exploitation in the next 30 days, from FIRST.org EPSS.
How urgent is this, really
Where this sits among everything scored
Real-World Exposure
moodle/moodleReal-time download stats are indexed for npm and PyPI packages. This vulnerability affects Packagist packages — download data is not available via public APIs for these ecosystems.
Description
Persistent XSS in /course/modedit.php of Moodle through 3.7.2 allows authenticated users (Teacher and above) to inject JavaScript into the session of another user (e.g., enrolled student or site administrator) via the introeditor[text] parameter. NOTE: the discoverer and vendor disagree on whether Moodle customers have a reasonable expectation that anyone authenticated as a Teacher can be trusted with the ability to add arbitrary JavaScript (this ability is not documented on Moodle's Teacher_role page). Because the vendor has this expectation, they have stated "this report has been closed as a false positive, and not a bug."
Affected Packages
| Ecosystem | Package | Vulnerable range | Fix |
|---|---|---|---|
| 🐘Packagist | moodle/moodle | ≥ 3.7 | No fix |
Affected Products
moodlemoodleDetection & mitigation playbook
Open-source dependencyDetect
Scan your dependency tree (package-lock.json, pnpm-lock.yaml, requirements.txt, go.sum, etc.) for moodle/moodle, including transitive dependencies — a direct dependency you never call can still pull in a vulnerable version.
Remediation status
The records we use list no patched version of moodle/moodle for CVE-2019-18210. Check the maintainer's advisory, and where your build allows, override or pin the dependency away from the vulnerable range.
Mitigate without a patch
Escape or sanitise the affected output on the server side rather than relying on client-side filtering, and add a Content-Security-Policy that blocks inline script execution so injected markup cannot run even if it reaches the page.
Frequently Asked Questions
Is CVE-2019-18210 in your dependencies?
Find it across Packagist, including transitive dependencies.