GHSA-vqqr-fgmh-f626
Contao Vulnerable to Cross-Site Scripting (XSS) through SVG uploads
EPSS Exploitation Probability
EPSS (Exploit Prediction Scoring System) is a daily probability model maintained by FIRST.org. It estimates the likelihood a CVE will be exploited in production environments within the next 30 days, derived from real-world threat intelligence signals.
Blast Radius
contao/core-bundle🐘contao/core-bundle🐘contao/core-bundleReal-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
Users can upload SVG files with malicious code, which is then executed in the back end and/or front end.
Patches
Update to Contao 4.13.54, 5.3.30 or 5.5.6.
Workarounds
Remove svg,svgz from the allowed upload file types in the system settings and from contao.editable_files in the config.yaml.
References
https://contao.org/en/security-advisories/cross-site-scripting-through-svg-uploads
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 | ≥ 4.0.0&&< 4.13.54 | 4.13.54 |
| 🐘Packagist | contao/core-bundle | ≥ 5.3.0&&< 5.3.30 | 5.3.30 |
| 🐘Packagist | contao/core-bundle | ≥ 5.4.0&&< 5.5.6 | 5.5.6 |
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 4.13.54 or later, then make sure no transitive (indirect) dependency still pins the vulnerable range — O3 confirms GHSA-vqqr-fgmh-f626 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-vqqr-fgmh-f626 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-vqqr-fgmh-f626. 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-vqqr-fgmh-f626 in your dependencies?
O3 detects GHSA-vqqr-fgmh-f626 across Packagist dependencies and uses function-level reachability to confirm whether the vulnerable code path is actually reachable — not just present. No false positives.