CVE-2026-33174 (High) detected in activestorage-8.0.4.gem

[mend-bolt-for-github]

CVE-2026-33174 - High Severity Vulnerability

Vulnerable Library - activestorage-8.0.4.gem

Attach cloud and local files in Rails applications.

Library home page: https://rubygems.org/gems/activestorage-8.0.4.gem

Path to dependency file: /Gemfile.lock

Path to vulnerable library: /tmp/containerbase/cache/.ruby/cache/activestorage-8.0.4.gem

Dependency Hierarchy:

• gettext_i18n_rails_js-1.3.1.gem (Root Library)
  • rails-8.0.4.gem
    • ❌ activestorage-8.0.4.gem (Vulnerable Library)

Found in base branch: master

Vulnerability Details

Active Storage allows users to attach cloud and local files in Rails applications. Prior to versions 8.1.2.1, 8.0.4.1, and 7.2.3.1, when serving files through Active Storage's proxy delivery mode, the proxy controller loads the entire requested byte range into memory before sending it. A request with a large or unbounded Range header (e.g. "bytes=0-") could cause the server to allocate memory proportional to the file size, possibly resulting in a DoS vulnerability through memory exhaustion. Versions 8.1.2.1, 8.0.4.1, and 7.2.3.1 contain a patch.

Publish Date: 2026-03-23

URL: CVE-2026-33174

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

Release Date: 2026-03-23

Fix Resolution: https://github.com/rails/rails.git - v8.0.4.1,https://github.com/rails/rails.git - v8.1.2.1,https://github.com/rails/rails.git - v7.2.3.1

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