CVE-2025-61921 (Medium) detected in sinatra-2.2.4.gem

## CVE-2025-61921 - Medium Severity Vulnerability
Vulnerable Library - sinatra-2.2.4.gem

Sinatra is a DSL for quickly creating web applications in Ruby with minimal effort.

Library home page: https://rubygems.org/gems/sinatra-2.2.4.gem

Path to dependency file: /Gemfile.lock

Path to vulnerable library: /home/wss-scanner/.gem/ruby/3.2.0/cache/sinatra-2.2.4.gem

Dependency Hierarchy:
- :x: **sinatra-2.2.4.gem** (Vulnerable Library)

Found in base branch: master

Vulnerability Details

Sinatra is a domain-specific language for creating web applications in Ruby. In versions prior to 4.2.0, there is a denial of service vulnerability in the "If-Match" and "If-None-Match" header parsing component of Sinatra, if the "etag" method is used when constructing the response. Carefully crafted input can cause "If-Match" and "If-None-Match" header parsing in Sinatra to take an unexpected amount of time, possibly resulting in a denial of service attack vector. This header is typically involved in generating the "ETag" header value. Any applications that use the "etag" method when generating a response are impacted. Version 4.2.0 fixes the issue.

Publish Date: 2025-10-10

URL: CVE-2025-61921

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

For more information on CVSS3 Scores, click here.

Suggested Fix

Type: Upgrade version

Origin: https://github.com/advisories/GHSA-mr3q-g2mv-mr4q

Release Date: 2025-10-10

Fix Resolution: sinatra - 4.2.0

***
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Start by reviewing /Gemfile.lock and the current sinatra-2.2.4.gem entry. Update the dependency to sinatra 4.2.0, then check whether the application has compatibility issues with that version. Done means the lockfile no longer selects the vulnerable version and the dependency upgrade is verified.

Written by the indexing model from the issue text.