GHSA-6qjx-787v-6pxr
MEDIUMCraft CMS stored XSS in indexedVolumes
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
craftcms/cmsReal-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
Summary
XSS can be triggered via the Update Asset Index utility
PoC
- Access setting tab
- Create new assets
- In assets name inject payload: "<script>alert(26)</script>
- Click Utilities tab
- Choose all volumes, or volume trigger xss
- Click Update asset indexes.
XSS will be triggered
Json response volumes name makes triggers the payload
"session":{"id":1,"indexedVolumes":{"1":"\"<script>alert(26)</script>"},
It’s run on every POST request in the utility.
Resolved in https://github.com/craftcms/cms/commit/8c2ad0bd313015b8ee42326af2848ee748f1d766
Affected Packages
| Ecosystem | Package | Vulnerable range | Fix |
|---|---|---|---|
| 🐘Packagist | craftcms/cms | ≥ 4.0.0-RC1&&< 4.4.6 | 4.4.6 |
Research use only. For defensive security, authorized penetration testing, and academic research only. Never execute exploit code against systems without explicit written authorization.
Detection & mitigation playbook
Open-source dependencyDetect
Scan your dependency tree (package-lock.json, pnpm-lock.yaml, requirements.txt, go.sum, etc.) for craftcms/cms. 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 craftcms/cms to 4.4.6 or later, then make sure no transitive (indirect) dependency still pins the vulnerable range — O3 confirms GHSA-6qjx-787v-6pxr 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-6qjx-787v-6pxr 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-6qjx-787v-6pxr. 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-6qjx-787v-6pxr in your dependencies?
O3 detects GHSA-6qjx-787v-6pxr across Packagist dependencies and uses function-level reachability to confirm whether the vulnerable code path is actually reachable — not just present. No false positives.