CVE-2026-34826 (Medium) detected in rack-3.2.4.gem

Vulnerable Library - rack-3.2.4.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-3.2.4.gem

Path to dependency file: /Gemfile.lock

Path to vulnerable library: /vendor/cache/rack-3.2.4.gem

Dependency Hierarchy:

• manageiq-style-1.5.9.gem (Root Library)
  • ❌ rack-3.2.4.gem (Vulnerable Library)

Found in base branch: master

Vulnerability Details

Rack is a modular Ruby web server interface. Prior to versions 2.2.23, 3.1.21, and 3.2.6, Rack::Utils.get_byte_ranges parses the HTTP Range header without limiting the number of individual byte ranges. Although the existing fix for CVE-2024-26141 rejects ranges whose total byte coverage exceeds the file size, it does not restrict the count of ranges. An attacker can supply many small overlapping ranges such as 0-0,0-0,0-0,... to trigger disproportionate CPU, memory, I/O, and bandwidth consumption per request. This results in a denial of service condition in Rack file-serving paths that process multipart byte range responses. This issue has been patched in versions 2.2.23, 3.1.21, and 3.2.6.

Publish Date: 2026-04-02

URL: CVE-2026-34826

CVSS 3 Score Details (5.3)

Base Score Metrics:

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

Suggested Fix

Type: Upgrade version

Origin: https://github.com/advisories/GHSA-x8cg-fq8g-mxfx

Release Date: 2026-04-02

Fix Resolution: rack - 3.2.6,rack - 3.1.21,rack - 2.2.23