CVE-2020-25813 — core
MEDIUMCVE-2020-25813 is a medium-severity (CVSS 5.3) vulnerability in mediawiki/core. A fix is available for mediawiki/core — see the affected versions and patch details below.
MediaWiki Special:UserRights exposes the existence of hidden users
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
mediawiki/core🐘mediawiki/coreReal-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
In MediaWiki before 1.31.10 and 1.32.x through 1.34.x before 1.34.4, Special:UserRights exposes the existence of hidden users.
Affected Packages
| Ecosystem | Package | Vulnerable range | Fix |
|---|---|---|---|
| 🐘Packagist | mediawiki/core | ≥ 1.31.0&&< 1.31.9 | 1.31.9composer require mediawiki/core:^1.31.9 |
| 🐘Packagist | mediawiki/core | ≥ 1.32.0&&< 1.34.3 | 1.34.3composer require mediawiki/core:^1.34.3 |
Affected Products
fedorafedoraprojectmediawikimediawikiDetection & mitigation playbook
Open-source dependencyDetect
Scan your dependency tree (package-lock.json, pnpm-lock.yaml, requirements.txt, go.sum, etc.) for mediawiki/core, including transitive dependencies — a direct dependency you never call can still pull in a vulnerable version.
Fix
Update mediawiki/core to 1.31.9 or later, then make sure no transitive (indirect) dependency still pins the vulnerable range — O3 confirms CVE-2020-25813 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.
Frequently Asked Questions
Is CVE-2020-25813 in your dependencies?
Find it across Packagist, including transitive dependencies.