CVE-2026-34829 (High) detected in rack-3.2.3.gem

## CVE-2026-34829 - High Severity Vulnerability
Vulnerable Library - rack-3.2.3.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-3.2.3.gem

Path to dependency file: /Gemfile.lock

Path to vulnerable library: /vendor/cache/rack-3.2.3.gem

Dependency Hierarchy:
- manageiq-style-1.5.9.gem (Root Library)
- :x: **rack-3.2.3.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::Multipart::Parser only wraps the request body in a BoundedIO when CONTENT_LENGTH is present. When a multipart/form-data request is sent without a Content-Length header, such as with HTTP chunked transfer encoding, multipart parsing continues until end-of-stream with no total size limit. For file parts, the uploaded body is written directly to a temporary file on disk rather than being constrained by the buffered in-memory upload limit. An unauthenticated attacker can therefore stream an arbitrarily large multipart file upload and consume unbounded disk space. This results in a denial of service condition for Rack applications that accept multipart form data. This issue has been patched in versions 2.2.23, 3.1.21, and 3.2.6.

Publish Date: 2026-04-02

URL: CVE-2026-34829

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: https://github.com/advisories/GHSA-8vqr-qjwx-82mw

Release Date: 2026-04-02

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

***
Step up your Open Source Security Game with Mend [here](https://www.whitesourcesoftware.com/full_solution_bolt_github)

Start by inspecting /Gemfile.lock and /vendor/cache/rack-3.2.3.gem to confirm how rack-3.2.3 is selected. Update the dependency to a patched Rack release, preferably 3.2.6, and verify that the lockfile and cached dependency no longer contain the vulnerable version.

Written by the indexing model from the issue text.