CVE-2026-33176 (High) detected in activesupport-8.0.3.gem

[mend-bolt-for-github]

CVE-2026-33176 - High Severity Vulnerability

Vulnerable Library - activesupport-8.0.3.gem

A toolkit of support libraries and Ruby core extensions extracted from the Rails framework. Rich support for multibyte strings, internationalization, time zones, and testing.

Library home page: https://rubygems.org/gems/activesupport-8.0.3.gem

Path to dependency file: /Gemfile.lock

Path to vulnerable library: /vendor/cache/activesupport-8.0.3.gem

Dependency Hierarchy:

• openid_connect-1.4.2.gem (Root Library)
  • json-jwt-1.17.0.gem
    • ❌ activesupport-8.0.3.gem (Vulnerable Library)

Found in base branch: master

Vulnerability Details

Active Support is a toolkit of support libraries and Ruby core extensions extracted from the Rails framework. Prior to versions 8.1.2.1, 8.0.4.1, and 7.2.3.1, Active Support number helpers accept strings containing scientific notation (e.g. "1e10000"), which "BigDecimal" expands into extremely large decimal representations. This can cause excessive memory allocation and CPU consumption when the expanded number is formatted, possibly resulting in a DoS vulnerability. Versions 8.1.2.1, 8.0.4.1, and 7.2.3.1 contain a patch.

Publish Date: 2026-03-23

URL: CVE-2026-33176

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-2j26-frm8-cmj9

Release Date: 2026-03-23

Fix Resolution: activesupport - 8.0.4.1,activesupport - 7.2.3.1,activesupport - 8.1.2.1

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