CVE-2024-21647

highpriority · track · 30EPSS 0.010 · 61 %ileDEEURUUS
grimoire priorityP2 · Scheduled
Exploitable?
—
no known exploitation
Likely / severe?
0.96% (61st) EPSS
CVSS 7.5 · high
Is it mine?
15 products
Check your exposure
Who says so?
6 sources
cnnvd · enisa_euvd · fstec_bdu · cert_bund

EPSS · scored 2026-10-27

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.

01

cvss

Technical severity, 0–10. One row per scoring source.

7.5
010

base score 0–10 · higher = more severe · hover a vector to decode⚠ sources disagree · medium–high · 5.9–7.5

v3.17.5highCVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:Hprimary · NVD / NIST USexploitability 3.9 · impact 3.6
v3.17.5highAV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:Hsecondary · FSTEC (BDU) RU
v3.15.9mediumCVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:N/I:N/A:Hsecondary · ENISA EU
v3.15.9mediumCVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:N/I:N/A:Hsecondary · security-advisories@github.comexploitability 2.2 · impact 3.6
v3.15.9mediumCVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:N/I:N/A:Hsecondary · OSV
v3.16.9mediumCVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H/E:Usecondary · CVSS-BT (t0sche)
02

ssvc

A stakeholder decision — act, attend, or track — from exploitation and impact.

Trackcoordinatorcisa_ssvcUS
03

weaknesses

The CWE weakness classes this flaw belongs to.

CWE-444USCWE-444USCWE-444US
04

affected products (15)

Products and version ranges known to be affected.

05

advisories (2)

Vendor and ecosystem advisories describing this.

  • WID-SEC-W-2024-0949Red Hat Satellite: Mehrere SchwachstellenDeutsch2024-04-23csaf · cert_bundDE

    Ein Angreifer kann mehrere Schwachstellen in Red Hat Satellite ausnutzen, um Sicherheitsmaßnahmen zu umgehen, einen Denial-of-Service-Zustand herbeizuführen, vertrauliche Informationen offenzulegen, Dateien zu manipulieren, HTTP-Request-Smuggling-Angriffe durchzuführen oder Phishing- und Cross-Site-Scripting (XSS)-Angriffe auszuführen.

  • GHSA-c2f4-cvqm-65w2Puma HTTP Request/Response Smuggling vulnerability2024-01-08ghsa · osvUS

    ### Impact Prior to versions 6.4.2 and 5.6.8, puma exhibited dangerous behavior when parsing chunked transfer encoding bodies. Fixed versions limit the size of chunk extensions. Without this limit, an attacker could cause unbounded resource (CPU, network bandwidth) consumption. ### Patches The vulnerability has been fixed in 6.4.2 and 5.6.8. ### Workarounds No known workarounds. ### References * [HTTP Request Smuggling](https://portswigger.net/web-security/request-smuggling) * Open an issue in [Puma](https://github.com/puma/puma) * See our [security policy](https://github.com/puma/puma/security/policy)

06

also known as (4)

Other names and identifiers for this entity.

07

sources

Which sources assert this record, and when.

cnnvdenisa_euvdfstec_bducert_bundnvdosvNVDCVE.orgMITRE
published 2024-01-08modified 2026-06-17
08

references (11)

External citations — patches, advisories, analysis.

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