GHSA-vvqw-fqwx-mqmm is a medium-severity (CVSS 5.4) Cross-site Scripting (XSS) vulnerability in decidim. O3 Security confirms whether GHSA-vvqw-fqwx-mqmm is actually reachable in your code before you act, and blocks exploitation at runtime until you patch.
Decidim::Admin vulnerable to cross-site scripting (XSS) in the admin panel with QuillJS WYSWYG editor
Real-World Exposure
decidimReal-time download stats are indexed for npm and PyPI packages. This vulnerability affects RubyGems packages — download data is not available via public APIs for these ecosystems.
Description
Impact
The WYSWYG editor QuillJS is subject to potential XSS attach in case the attacker manages to modify the HTML before being uploaded to the server.
The attacker is able to change e.g. to <svg onload=alert('XSS')> if they know how to craft these requests themselves.
Patches
N/A
Workarounds
Review the user accounts that have access to the admin panel (i.e. general Administrators, and participatory space's Administrators) and remove access to them if they don't need it.
Disable the "Enable rich text editor for participants" setting in the admin dashboard
References
OWASP ASVS v4.0.3-5.1.3
Affected Packages
| Ecosystem | Package | Vulnerable range | Fix |
|---|---|---|---|
| 💎RubyGems | decidim | all versions | 0.27.7 |
Detection & mitigation playbook
Open-source dependencyDetect
Scan your dependency tree (package-lock.json, pnpm-lock.yaml, requirements.txt, go.sum, etc.) for decidim. 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 decidim to 0.27.7 or later, then make sure no transitive (indirect) dependency still pins the vulnerable range — O3 confirms GHSA-vvqw-fqwx-mqmm 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-vvqw-fqwx-mqmm 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-vvqw-fqwx-mqmm. 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-vvqw-fqwx-mqmm in your dependencies?
O3 detects GHSA-vvqw-fqwx-mqmm across RubyGems dependencies and uses function-level reachability to confirm whether the vulnerable code path is actually reachable — not just present. No false positives.