GHSA-4xh9-5vh8-3p58 is a medium-severity (CVSS 6.1) Cross-site Scripting (XSS) vulnerability in yiisoft/yii2. A fix is available for yiisoft/yii2 — 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
Where this sits among everything scored
Real-World Exposure
yiisoft/yii2Real-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
Reflected Cross-site scripting (XSS) vulnerability in Yii Framework before 2.0.11, when development mode is used, allows remote attackers to inject arbitrary web script or HTML via crafted request data that is mishandled on the debug-mode exception screen.
Affected Packages
| Ecosystem | Package | Vulnerable range | Fix |
|---|---|---|---|
| 🐘Packagist | yiisoft/yii2 | all versions | 2.0.11composer require yiisoft/yii2:^2.0.11 |
Affected Products
yiiyii_softwareDetection & mitigation playbook
Open-source dependencyDetect
Scan your dependency tree (package-lock.json, pnpm-lock.yaml, requirements.txt, go.sum, etc.) for yiisoft/yii2, including transitive dependencies — a direct dependency you never call can still pull in a vulnerable version.
Fix
Update yiisoft/yii2 to 2.0.11 or later, then make sure no transitive (indirect) dependency still pins the vulnerable range — O3 confirms GHSA-4xh9-5vh8-3p58 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-4xh9-5vh8-3p58 in your dependencies?
Find it across Packagist, including transitive dependencies.