CVE-2020-25911 is a critical-severity (CVSS 9.1) XML External Entity (XXE) vulnerability in modx/revolution. 1 public exploit reference exists, so weaponization risk is real. A fix is available for modx/revolution — see the affected versions and patch details below.
XML External Entity vulnerability in MODX CMS
EPSS Exploitation Probability
Probability of exploitation in the next 30 days, from FIRST.org EPSS.
How urgent is this, really
CVE-2020-25911 by exploitation likelihood (EPSS) against impact (CVSS). Outside the shaded patch-first corner.
Where this sits among everything scored
Of 385,738 CVEs with a current EPSS score, this one falls in the < 10% band (highlighted). Counts from FIRST.org, log-scaled.
Real-World Exposure
modx/revolutionReal-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
A XML External Entity (XXE) vulnerability was discovered in the modRestServiceRequest component in MODX CMS 2.7.3 which can lead to an information disclosure or denial of service (DOS).
Affected Packages
| Ecosystem | Package | Vulnerable range | Fix |
|---|---|---|---|
| 🐘Packagist | modx/revolution | all versions | 2.8.0composer require modx/revolution:^2.8.0 |
Affected Products
modx revolutionmodxResearch 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 modx/revolution, including transitive dependencies — a direct dependency you never call can still pull in a vulnerable version.
Fix
Update modx/revolution to 2.8.0 or later, then make sure no transitive (indirect) dependency still pins the vulnerable range — O3 confirms CVE-2020-25911 is resolved across your whole dependency graph.
Workarounds
Assume what was exposed is already known: rotate any credential, token or key that the affected component could return, restrict the endpoint to callers that genuinely need it, and strip sensitive fields from responses and error output at the boundary rather than relying on the client not to read them.
Frequently Asked Questions
Is CVE-2020-25911 in your dependencies?
Find it across Packagist, including transitive dependencies.