GHSA-mcxr-fx5f-96qq — concrete5/core
GHSA-mcxr-fx5f-96qq is a Server-Side Request Forgery (SSRF) vulnerability in concrete5/core. A fix is available for concrete5/core — see the affected versions and patch details below.
Server-Side Request Forgery in Concrete CMS
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.
Real-World Exposure
concrete5/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
Concrete CMS (formerly concrete5) versions below 8.5.7 has a SSRF mitigation bypass using DNS Rebind attack giving an attacker the ability to fetch cloud IAAS (ex AWS) IAM keys.To fix this Concrete CMS no longer allows downloads from the local network and specifies the validated IP when downloading rather than relying on DNS.Discoverer: Adrian Tiron from FORTBRIDGE ( https://www.fortbridge.co.uk/ )The Concrete CMS team gave this a CVSS 3.1 score of 3.5 AV:N/AC:H/PR:L/UI:N/S:C/C:L/I:N/A:N . Please note that Cloud IAAS provider mis-configurations are not Concrete CMS vulnerabilities. A mitigation for this vulnerability is to make sure that the IMDS configurations are according to a cloud provider's best practices.This fix is also in Concrete version 9.0.0
Affected Packages
| Ecosystem | Package | Vulnerable range | Fix |
|---|---|---|---|
| 🐘Packagist | concrete5/core | all versions | 8.5.7composer require concrete5/core:^8.5.7 |
Detection & mitigation playbook
Open-source dependencyDetect
Scan your dependency tree (package-lock.json, pnpm-lock.yaml, requirements.txt, go.sum, etc.) for concrete5/core, including transitive dependencies — a direct dependency you never call can still pull in a vulnerable version.
Fix
Update concrete5/core to 8.5.7 or later, then make sure no transitive (indirect) dependency still pins the vulnerable range — O3 confirms GHSA-mcxr-fx5f-96qq 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 Security's impact-aware SCA analyses which vulnerable code paths your application actually calls, so a match like GHSA-mcxr-fx5f-96qq can be triaged on real exposure rather than presence alone.
Tailored to GHSA-mcxr-fx5f-96qq. 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-mcxr-fx5f-96qq in your dependencies?
O3 Security finds GHSA-mcxr-fx5f-96qq across Packagist dependencies, including transitive ones, and its impact-aware SCA ranks findings by whether your code actually calls the vulnerable path.