GHSA-gqqf-g5r7-84vf
MEDIUMTYPO3 HTML Sanitizer Bypasses Cross-Site Scripting Protection
Blast Radius
typo3/cms-core🐘typo3/cms-core🐘typo3/cms-core🐘typo3/cms-core🐘typo3/cms-coreReal-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
Meta
- CVSS:
CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:C/C:L/I:L/A:N/E:F/RL:O/RC:C(5.7)
Problem
Due to a parsing issue in upstream package masterminds/html5, malicious markup used in a sequence with special HTML comments cannot be filtered and sanitized. This allows to by-pass the cross-site scripting mechanism of typo3/html-sanitizer.
Solution
Update to TYPO3 version 7.6.58 ELTS, 8.7.48 ELTS, 9.5.37 ELTS, 10.4.32 or 11.5.16 that fix the problem described above.
Credits
Thanks to David Klein who reported this issue, and to TYPO3 security team member Oliver Hader who fixed the issue.
References
Affected Packages
| Ecosystem | Package | Vulnerable range | Fix |
|---|---|---|---|
| 🐘Packagist | typo3/cms-core | ≥ 7.0.0&&< 7.6.58 | 7.6.58 |
| 🐘Packagist | typo3/cms-core | ≥ 8.0.0&&< 8.7.48 | 8.7.48 |
| 🐘Packagist | typo3/cms-core | ≥ 9.0.0&&< 9.5.37 | 9.5.37 |
| 🐘Packagist | typo3/cms-core | ≥ 10.0.0&&< 10.4.32 | 10.4.32 |
| 🐘Packagist | typo3/cms-core | ≥ 11.0.0&&< 11.5.16 | 11.5.16 |
Detection & mitigation playbook
Open-source dependencyDetect
Scan your dependency tree (package-lock.json, pnpm-lock.yaml, requirements.txt, go.sum, etc.) for typo3/cms-core. 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 typo3/cms-core to 7.6.58 or later, then make sure no transitive (indirect) dependency still pins the vulnerable range — O3 confirms GHSA-gqqf-g5r7-84vf 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-gqqf-g5r7-84vf 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-gqqf-g5r7-84vf. 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-gqqf-g5r7-84vf in your dependencies?
O3 detects GHSA-gqqf-g5r7-84vf across Packagist dependencies and uses function-level reachability to confirm whether the vulnerable code path is actually reachable — not just present. No false positives.