CVE-2025-27400 is a low-severity (CVSS 2.9) vulnerability in openmage/magento-lts. A fix is available for openmage/magento-lts — see the affected versions and patch details below.
Magento vulnerable to stored XSS in theme config fields
Exploitation Status
No confirmed exploitation observed yet
- CISA’s own triage has not observed active exploitation or public proof-of-concept code for this CVE as of its last assessment.
Exploitation and automatability from CISA’s SSVC triage for CVE-2025-27400.
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.
How urgent is this, really
CVE-2025-27400 plotted by exploitation likelihood (EPSS) against impact (CVSS). The shaded corner — EPSS 50%+ and CVSS 7.0+ — is where this CVE doesn't sit, though severity or exploitability alone can still warrant action.
Where this sits among everything scored
Of 378,567 CVEs with a current EPSS score, this one falls in the < 10% band (highlighted). Real counts from FIRST.org, not a sample — log-scaled since the landscape is heavily right-skewed.
Real-World Exposure
openmage/magento-ltsReal-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 Long Term Support (LTS) is an unofficial, community-driven project provides an alternative to the Magento Community Edition e-commerce platform with a high level of backward compatibility. Versions prior to 20.12.3 and 20.13.0 contain a vulnerability that allows script execution in the admin panel which could lead to cross-site scripting against authenticated admin users. The attack requires an admin user with configuration access, so in practicality it is not very likely to be useful given that a user with this level of access is probably already a full admin. Versions 20.12.3 and 20.13.0 contain a patch for the issue.
Affected Packages
| Ecosystem | Package | Vulnerable range | Fix |
|---|---|---|---|
| 🐘Packagist | openmage/magento-lts | all versions | 20.12.3composer require openmage/magento-lts:^20.12.3 |
Detection & mitigation playbook
Open-source dependencyDetect
Scan your dependency tree (package-lock.json, pnpm-lock.yaml, requirements.txt, go.sum, etc.) for openmage/magento-lts, including transitive dependencies — a direct dependency you never call can still pull in a vulnerable version.
Fix
Update openmage/magento-lts to 20.12.3 or later, then make sure no transitive (indirect) dependency still pins the vulnerable range — O3 confirms CVE-2025-27400 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 CVE-2025-27400 can be triaged on real exposure rather than presence alone.
Tailored to CVE-2025-27400. Runtime protection reduces exposure until a permanent patch is applied and verified — it complements patching, it doesn't replace it.
Frequently Asked Questions
Is CVE-2025-27400 in your dependencies?
O3 Security finds CVE-2025-27400 across Packagist dependencies, including transitive ones, and its impact-aware SCA ranks findings by whether your code actually calls the vulnerable path.