[DRE-maint] Bug#1118290: ruby-sinatra: CVE-2025-61921

[Salvatore Bonaccorso]

Source: ruby-sinatra
Version: 4.1.1-5
Severity: important
Tags: security upstream
X-Debbugs-Cc: carnil at debian.org, Debian Security Team <team at security.debian.org>
Control: found -1 4.1.1-6

Hi,

The following vulnerability was published for ruby-sinatra.

CVE-2025-61921[0]:
| 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.


If you fix the vulnerability please also make sure to include the
CVE (Common Vulnerabilities & Exposures) id in your changelog entry.

For further information see:

[0] https://security-tracker.debian.org/tracker/CVE-2025-61921
    https://www.cve.org/CVERecord?id=CVE-2025-61921
[1] https://github.com/sinatra/sinatra/security/advisories/GHSA-mr3q-g2mv-mr4q
[2] https://github.com/sinatra/sinatra/issues/2120
[3] https://github.com/sinatra/sinatra/pull/1823
[4] https://github.com/sinatra/sinatra/pull/2121
[5] https://bugs.ruby-lang.org/issues/19104

Please adjust the affected versions in the BTS as needed.

Regards,
Salvatore