Vulnerability · Published Feb 18, 2026 · Assigned by GitHub_M
CVE-2026-25500Rack's Stored XSS in Rack::Directory via javascript: filenames rendered into anchor href
Medium 5.4
In plain English
A medium-severity cross-site scripting in rack from rack. There are no confirmed reports of exploitation so far. The chance it is exploited in the next 30 days is estimated at 0.3% (higher than 19% of all known vulnerabilities). Fixed versions are available - upgrade the affected package.
Official 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.
Affected packages & fixed versions
| Ecosystem | Package | Fixed in | Advisory |
|---|---|---|---|
| Debian:12 | ruby-rack | 2.2.22-0+deb12u1 | DEBIAN-CVE-2026-25500 |
| Debian:12 | ruby-rack | 2.2.22-0+deb12u1 | DSA-6180-1 |
| Debian:13 | ruby-rack | 3.1.20-0+deb13u1 | DEBIAN-CVE-2026-25500 |
| Debian:13 | ruby-rack | 3.1.20-0+deb13u1 | DSA-6180-1 |
| Debian:14 | ruby-rack | 3.2.5-1 | DEBIAN-CVE-2026-25500 |
| RubyGems | rack | 3.1.20 | GHSA-whrj-4476-wvmp |
| RubyGems | rack | 2.2.22 | GHSA-whrj-4476-wvmp |
| RubyGems | rack | 3.2.5 | GHSA-whrj-4476-wvmp |
| Ubuntu:24.04:LTS | ruby-rack | 2.2.7-1ubuntu0.6 | UBUNTU-CVE-2026-25500 |
| Ubuntu:25.10 | ruby-rack | 3.1.16-0.1ubuntu0.2 | UBUNTU-CVE-2026-25500 |
| Ubuntu:26.04:LTS | ruby-rack | 3.2.4-1ubuntu1 | UBUNTU-CVE-2026-25500 |
| Ubuntu:26.10 | ruby-rack | 3.2.4-1ubuntu1 | UBUNTU-CVE-2026-25500 |
Affected products (as reported)
Weakness: CWE-79 · Vector: CVSS:3.1/AV:N/AC:L/PR:L/UI:R/S:C/C:L/I:L/A:N
References
- https://github.com/rack/rack/security/advisories/GHSA-whrj-4476-wvmp x_refsource_CONFIRM
- https://github.com/rack/rack/commit/f2f225f297b99fbee3d9f51255d41f601fc40aff x_refsource_MISC