GHSA-hf9p-9r39-r2h3 is a high-severity (CVSS 7.2) Unrestricted File Upload vulnerability in concrete5/concrete5. 1 public exploit reference exists, so weaponization risk is real. A fix is available for concrete5/concrete5 — see the affected versions and patch details below.
EPSS Exploitation Probability
Probability of exploitation in the next 30 days, from FIRST.org EPSS.
How urgent is this, really
GHSA-hf9p-9r39-r2h3 by exploitation likelihood (EPSS) against impact (CVSS). Outside the shaded patch-first corner.
Where this sits among everything scored
Of 385,738 CVEs with a current EPSS score, this one falls in the < 10% band (highlighted). Counts from FIRST.org, log-scaled.
Real-World Exposure
concrete5/concrete5Real-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
Concrete5 before 8.5.3 allows Unrestricted Upload of File with Dangerous Type such as a .phar file.
Affected Packages
| Ecosystem | Package | Vulnerable range | Fix |
|---|---|---|---|
| 🐘Packagist | concrete5/concrete5 | all versions | 8.5.3composer require concrete5/concrete5:^8.5.3 |
Affected Products
concrete cmsconcretecmsResearch 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 concrete5/concrete5, including transitive dependencies — a direct dependency you never call can still pull in a vulnerable version.
Fix
Update concrete5/concrete5 to 8.5.3 or later, then make sure no transitive (indirect) dependency still pins the vulnerable range — O3 confirms GHSA-hf9p-9r39-r2h3 is resolved across your whole dependency graph.
Workarounds
Treat uploaded files as untrusted until proven otherwise: validate the actual content type rather than the supplied extension, store uploads outside the web root on a volume mounted without execute permission, and rename them to server-generated identifiers so an attacker cannot choose the path a request will later resolve.
Frequently Asked Questions
Is GHSA-hf9p-9r39-r2h3 in your dependencies?
Find it across Packagist, including transitive dependencies.