GHSA-4w4j-9533-82qg
MEDIUMGHSA-4w4j-9533-82qg is a medium-severity (CVSS 6.1) Cross-site Scripting (XSS) vulnerability in moodle/moodle. O3 Security confirms whether GHSA-4w4j-9533-82qg is actually reachable in your code before you act, and blocks exploitation at runtime until you patch.
Moodle Cross-site Scripting (XSS)
Real-World Exposure
moodle/moodle🐘moodle/moodle🐘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
A vulnerability was found in Moodle 3.9 to 3.9.1, 3.8 to 3.8.4 and 3.7 to 3.7.7 where it was possible to include JavaScript in a book's chapter title, which was not escaped on the "Add new chapter" page. This is fixed in 3.9.2, 3.8.5 and 3.7.8.
Affected Packages
| Ecosystem | Package | Vulnerable range | Fix |
|---|---|---|---|
| 🐘Packagist | moodle/moodle | ≥ 3.9&&< 3.9.2 | 3.9.2 |
| 🐘Packagist | moodle/moodle | ≥ 3.8&&< 3.8.5 | 3.8.5 |
| 🐘Packagist | moodle/moodle | ≥ 3.7&&< 3.7.8 | 3.7.8 |
Detection & mitigation playbook
Open-source dependencyDetect
Scan your dependency tree (package-lock.json, pnpm-lock.yaml, requirements.txt, go.sum, etc.) for moodle/moodle. O3's reachability analysis confirms whether the vulnerable code path is actually invoked in your application, so you act on real exposure instead of every transitive match.
Fix
Update moodle/moodle to 3.9.2 or later, then make sure no transitive (indirect) dependency still pins the vulnerable range — O3 confirms GHSA-4w4j-9533-82qg is resolved across your whole dependency graph.
Workarounds
If you can't upgrade right away: gate or disable the affected feature, validate untrusted input at the boundary, and avoid passing attacker-controlled data into the vulnerable path. O3's runtime protection blocks exploitation in production as an interim safeguard until the upgrade lands.
How O3 protects you
O3 pinpoints whether GHSA-4w4j-9533-82qg is reachable in your code and exactly where to fix it, then blocks exploitation in production at runtime until the patched version is deployed.
Tailored to GHSA-4w4j-9533-82qg. Runtime protection reduces exposure until a permanent patch is applied and verified — it complements patching, it doesn't replace it.
Frequently Asked Questions
Is GHSA-4w4j-9533-82qg in your dependencies?
O3 detects GHSA-4w4j-9533-82qg across Packagist dependencies and uses function-level reachability to confirm whether the vulnerable code path is actually reachable — not just present. No false positives.