GHSA-39ch-rg26-gmq5 is a medium-severity (CVSS 6.9) Cross-site Scripting (XSS) vulnerability in magento/community-edition. A fix is available for magento/community-edition — see the affected versions and patch details below.
Magento DOM-based Cross-Site Scripting vulnerability on mage-messages cookies
EPSS Exploitation Probability
Probability of exploitation in the next 30 days, from FIRST.org EPSS.
How urgent is this, really
GHSA-39ch-rg26-gmq5 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
magento/community-edition🐘magento/community-edition🐘magento/project-community-editionReal-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
Magento versions 2.4.2 (and earlier), 2.4.1-p1 (and earlier) and 2.3.6-p1 (and earlier) are affected by a DOM-based Cross-Site Scripting vulnerability on mage-messages cookies. Successful exploitation could lead to arbitrary JavaScript execution by an unauthenticated attacker. User interaction is required for successful exploitation.
Affected Packages
| Ecosystem | Package | Vulnerable range | Fix |
|---|---|---|---|
| 🐘Packagist | magento/community-edition | ≥ 2.4.0&&< 2.4.2-p1 | 2.4.2-p1composer require magento/community-edition:^2.4.2-p1 |
| 🐘Packagist | magento/community-edition | all versions | 2.3.7composer require magento/community-edition:^2.3.7 |
| 🐘Packagist | magento/project-community-edition | all versions | No fix |
Affected Products
magentomagentoDetection & mitigation playbook
Open-source dependencyDetect
Scan your dependency tree (package-lock.json, pnpm-lock.yaml, requirements.txt, go.sum, etc.) for magento/community-edition, including transitive dependencies — a direct dependency you never call can still pull in a vulnerable version.
Fix
Update magento/community-edition to 2.4.2-p1 or later, then make sure no transitive (indirect) dependency still pins the vulnerable range — O3 confirms GHSA-39ch-rg26-gmq5 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-39ch-rg26-gmq5 in your dependencies?
Find it across Packagist, including transitive dependencies.