CVE-2024-21647

5.9 MEDIUM
Published: January 08, 2024 Modified: November 03, 2025

Description

Puma is a web server for Ruby/Rack applications built for parallelism. Prior to version 6.4.2, puma exhibited incorrect behavior when parsing chunked transfer encoding bodies in a way that allowed HTTP request smuggling. Fixed versions limits the size of chunk extensions. Without this limit, an attacker could cause unbounded resource (CPU, network bandwidth) consumption. This vulnerability has been fixed in versions 6.4.2 and 5.6.8.

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CVSS v3.x Details

0.0 Low Medium High Critical 10.0
Vector String
CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:N/I:N/A:H

References to Advisories, Solutions, and Tools

Patch Vendor Advisory Exploit Third Party Advisory
https://github.com/puma/puma/security/advisories/GHSA-c2f4-cvqm-65w2
Source: security-advisories@github.com
Vendor Advisory
https://github.com/puma/puma/security/advisories/GHSA-c2f4-cvqm-65w2
Source: af854a3a-2127-422b-91ae-364da2661108
Vendor Advisory

5 reference(s) from NVD

Quick Stats

CVSS v3 Score
5.9 / 10.0
EPSS (Exploit Probability)
2.0%
83th percentile
Exploitation Status
Not in CISA KEV

Weaknesses (CWE)

Affected Vendors

puma