GHSA-2cv6-6437-39p2 is a medium-severity (CVSS 4.8) Unrestricted File Upload vulnerability in microweber/microweber. 1 public exploit reference exists, so weaponization risk is real. A fix is available for microweber/microweber — see the affected versions and patch details below.
Cross-site Scripting in microweber
EPSS Exploitation Probability
Probability of exploitation in the next 30 days, from FIRST.org EPSS.
How urgent is this, really
GHSA-2cv6-6437-39p2 by exploitation likelihood (EPSS) against impact (CVSS). Outside the shaded patch-first corner.
Where this sits among everything scored
Of 379,842 CVEs with a current EPSS score, this one falls in the < 10% band (highlighted). Counts from FIRST.org, log-scaled.
Real-World Exposure
microweber/microweberReal-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
File upload filter bypass leading to stored XSS in GitHub repository microweber/microweber prior to 1.2.12.
Affected Packages
| Ecosystem | Package | Vulnerable range | Fix |
|---|---|---|---|
| 🐘Packagist | microweber/microweber | all versions | 1.2.12composer require microweber/microweber:^1.2.12 |
Affected Products
microwebermicroweberResearch 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 microweber/microweber, including transitive dependencies — a direct dependency you never call can still pull in a vulnerable version.
Fix
Update microweber/microweber to 1.2.12 or later, then make sure no transitive (indirect) dependency still pins the vulnerable range — O3 confirms GHSA-2cv6-6437-39p2 is resolved across your whole dependency graph.
Workarounds
Escape or sanitise the affected output on the server side rather than relying on client-side filtering, and add a Content-Security-Policy that blocks inline script execution so injected markup cannot run even if it reaches the page.
Frequently Asked Questions
Is GHSA-2cv6-6437-39p2 in your dependencies?
Find it across Packagist, including transitive dependencies.