CVE-2026-25500 (Medium) detected in rack-3.1.16.gem

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CVE-2026-25500 - Medium Severity Vulnerability

Vulnerable Library - rack-3.1.16.gem

Rack provides a minimal, modular and adaptable interface for developing web applications in Ruby. By wrapping HTTP requests and responses in the simplest way possible, it unifies and distills the API for web servers, web frameworks, and software in between (the so-called middleware) into a single method call.

Library home page: https://rubygems.org/gems/rack-3.1.16.gem

Path to dependency file: /Gemfile.lock

Path to vulnerable library: /vendor/cache/rack-3.1.16.gem

Dependency Hierarchy:

• manageiq-style-1.3.3.gem (Root Library)
  • rubocop-rails-2.32.0.gem
    • ❌ rack-3.1.16.gem (Vulnerable Library)

Found in base branch: master

Vulnerability Details

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.

Publish Date: 2026-02-18

URL: CVE-2026-25500

CVSS 3 Score Details (5.4)

Base Score Metrics:

• Exploitability Metrics:
  • Attack Vector: Network
  • Attack Complexity: Low
  • Privileges Required: Low
  • User Interaction: Required
  • Scope: Changed
• Impact Metrics:
  • Confidentiality Impact: Low
  • Integrity Impact: Low
  • Availability Impact: None

For more information on CVSS3 Scores, click here.

Suggested Fix

Type: Upgrade version

Release Date: 2026-02-17

Fix Resolution: https://github.com/rack/rack.git - v2.2.22,https://github.com/rack/rack.git - v3.2.5,https://github.com/rack/rack.git - v3.1.20

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