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National Vulnerability Database

National Vulnerability Database

NVD

National Vulnerability Database
  1. Vulnerabilities

CVE-2025-61921 Detail

Description

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.


Metrics

 
NVD enrichment efforts reference publicly available information to associate vector strings. CVSS information contributed by other sources is also displayed.
CVSS 4.0 Severity and Vector Strings:

NIST CVSS score
NIST: NVD
N/A
NVD assessment not yet provided.

Nist CVSS score does not match with CNA score
CNA:  GitHub, Inc.
CVSS-BT 2.7 LOW
Vector:  CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:N/VI:N/VA:L/SC:N/SI:N/SA:N/E:U

References to Advisories, Solutions, and Tools

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URL Source(s) Tag(s)
https://bugs.ruby-lang.org/issues/19104 GitHub, Inc.
https://github.com/sinatra/sinatra/issues/2120 GitHub, Inc.
https://github.com/sinatra/sinatra/pull/1823 GitHub, Inc.
https://github.com/sinatra/sinatra/pull/2121 GitHub, Inc.
https://github.com/sinatra/sinatra/security/advisories/GHSA-mr3q-g2mv-mr4q GitHub, Inc.

Weakness Enumeration

CWE-ID CWE Name Source
CWE-1333 Inefficient Regular Expression Complexity GitHub, Inc.  

Change History

1 change records found show changes

Quick Info

CVE Dictionary Entry:
CVE-2025-61921
NVD Published Date:
10/10/2025
NVD Last Modified:
10/14/2025
Source:
GitHub, Inc.