CVE-2025-61919 (High) detected in rack-2.2.19.gem

[mend-bolt-for-github]

CVE-2025-61919 - High Severity Vulnerability

Vulnerable Library - rack-2.2.19.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-2.2.19.gem

Path to dependency file: /Gemfile.lock

Path to vulnerable library: /Gemfile.lock

Dependency Hierarchy:

• sidecloq-0.5.0.gem (Root Library)
  • sidekiq-7.3.9.gem
    • ❌ rack-2.2.19.gem (Vulnerable Library)

Found in base branch: master

Vulnerability Details

Rack is a modular Ruby web server interface. Prior to versions 2.2.20, 3.1.18, and 3.2.3, "Rack::Request#POST" reads the entire request body into memory for "Content-Type: application/x-www-form-urlencoded", calling "rack.input.read(nil)" without enforcing a length or cap. Large request bodies can therefore be buffered completely into process memory before parsing, leading to denial of service (DoS) through memory exhaustion. Users should upgrade to Rack version 2.2.20, 3.1.18, or 3.2.3, anu of which enforces form parameter limits using "query_parser.bytesize_limit", preventing unbounded reads of "application/x-www-form-urlencoded" bodies. Additionally, enforce strict maximum body size at the proxy or web server layer (e.g., Nginx "client_max_body_size", Apache "LimitRequestBody").

Publish Date: 2025-10-10

URL: CVE-2025-61919

CVSS 3 Score Details (7.5)

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: High

For more information on CVSS3 Scores, click here.

Suggested Fix

Type: Upgrade version

Origin: GHSA-6xw4-3v39-52mm

Release Date: 2025-10-10

Fix Resolution: rack - 3.1.18,rack - 3.2.3,rack - 2.2.20

---

Step up your Open Source Security Game with Mend here