Detections
Analytics
CVE-2026-25500
medium
Description
Rack is a modular Ruby web server interface. Prior to versions 2.2.22, 3.1.20, and 3.2.5, `Rack::Directory` generates an HTML directory index where each file entry is rendered as a clickable link. If a file exists on disk whose basename starts with the `javascript:` scheme (e.g. `javascript:alert(1)`), the generated index contains an anchor whose `href` is exactly `javascript:alert(1)`. Clicking the entry executes JavaScript in the browser (demonstrated with `alert(1)`). Versions 2.2.22, 3.1.20, and 3.2.5 fix the issue.
References
https://github.com/rack/rack/security/advisories/GHSA-whrj-4476-wvmp
https://github.com/rack/rack/commit/f2f225f297b99fbee3d9f51255d41f601fc40aff