GHSA-h58v-c6rf-g9f7
MEDIUMGHSA-h58v-c6rf-g9f7 is a medium-severity (CVSS 6.1) Cross-site Scripting (XSS) vulnerability in contao/core-bundle. O3 Security confirms whether GHSA-h58v-c6rf-g9f7 is actually reachable in your code before you act, and blocks exploitation at runtime until you patch.
Cross site scripting in the system log
Real-World Exposure
contao/core-bundle🐘contao/core-bundle🐘contao/contao🐘contao/contaoReal-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
Impact
It is possible to inject code into the tl_log table that will be executed in the browser when the system log is called in the back end.
Patches
Update to Contao 4.9.16 or 4.11.5.
Workarounds
Disable the system log module in the back end for all users (especially admin users).
References
https://contao.org/en/security-advisories/cross-site-scripting-in-the-system-log-2021
For more information
If you have any questions or comments about this advisory, open an issue in contao/contao.
Affected Packages
| Ecosystem | Package | Vulnerable range | Fix |
|---|---|---|---|
| 🐘Packagist | contao/core-bundle | ≥ 4.5.0&&< 4.9.16 | 4.9.16 |
| 🐘Packagist | contao/core-bundle | ≥ 4.10.0&&< 4.11.5 | 4.11.5 |
| 🐘Packagist | contao/contao | ≥ 4.5.0&&< 4.9.16 | 4.9.16 |
| 🐘Packagist | contao/contao | ≥ 4.10.0&&< 4.11.5 | 4.11.5 |
Detection & mitigation playbook
Open-source dependencyDetect
Scan your dependency tree (package-lock.json, pnpm-lock.yaml, requirements.txt, go.sum, etc.) for contao/core-bundle. 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 contao/core-bundle to 4.9.16 or later, then make sure no transitive (indirect) dependency still pins the vulnerable range — O3 confirms GHSA-h58v-c6rf-g9f7 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-h58v-c6rf-g9f7 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-h58v-c6rf-g9f7. 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-h58v-c6rf-g9f7 in your dependencies?
O3 detects GHSA-h58v-c6rf-g9f7 across Packagist dependencies and uses function-level reachability to confirm whether the vulnerable code path is actually reachable — not just present. No false positives.