GHSA-rhx4-hvx9-j387 is a medium-severity (CVSS 5.4) Cross-site Scripting (XSS) vulnerability in silverstripe/framework. O3 Security confirms whether GHSA-rhx4-hvx9-j387 is actually reachable in your code before you act, and blocks exploitation at runtime until you patch.
Silverstripe Framework has a XSS vulnerability in HTML editor
Real-World Exposure
silverstripe/frameworkReal-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
A bad actor with access to edit content in the CMS could send a specifically crafted encoded payload to the server, which could be used to inject a JavaScript payload on the front end of the site. The payload would be sanitised on the client-side, but server-side sanitisation doesn't catch it.
The server-side sanitisation logic has been updated to sanitise against this attack.
Reported by
James Nicoll from Fujitsu Cyber
References
Affected Packages
| Ecosystem | Package | Vulnerable range | Fix |
|---|---|---|---|
| 🐘Packagist | silverstripe/framework | all versions | 5.3.23 |
Detection & mitigation playbook
Open-source dependencyDetect
Scan your dependency tree (package-lock.json, pnpm-lock.yaml, requirements.txt, go.sum, etc.) for silverstripe/framework. 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 silverstripe/framework to 5.3.23 or later, then make sure no transitive (indirect) dependency still pins the vulnerable range — O3 confirms GHSA-rhx4-hvx9-j387 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-rhx4-hvx9-j387 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-rhx4-hvx9-j387. 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-rhx4-hvx9-j387 in your dependencies?
O3 detects GHSA-rhx4-hvx9-j387 across Packagist dependencies and uses function-level reachability to confirm whether the vulnerable code path is actually reachable — not just present. No false positives.