Skip to main content

Boteraser | Website and Server Security Solutions

🛡️ CVE-2024-21647 — puma

🟡 CVSS 5.9 — Medium ✅ No Known Exploit CWE-444 OSV
5.9
CVSS Score
0 Low4 Medium7 High9 Critical10

Description

Puma HTTP Request/Response Smuggling vulnerability

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)

How this vulnerability can be exploited

This issue can be reached over the network, attack complexity is high, an attacker needs no privileges on the target. No user interaction is required. The scope is unchanged, so the impact stays within the vulnerable component. Rated impact: confidentiality none, integrity none, availability high.

CVSS metrics in full

The score comes from this vector: CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:N/I:N/A:H

  • Attack vector: Network — reachable from anywhere that can route to the service.
  • Attack complexity: High — the attacker first has to win a race, learn a secret or otherwise prepare the target.
  • Privileges required: None — an unauthenticated stranger can try it.
  • User interaction: None — nobody has to be tricked into anything.
  • Scope: Unchanged — the damage stays inside the vulnerable component.
  • Confidentiality impact: None.
  • Integrity impact: None.
  • Availability impact: High — total loss, or loss the attacker controls.

Weakness class

CVE-2024-21647 is classified as CWE-444: HTTP Request Smuggling. A proxy and a server disagree on where one request ends, letting an attacker slip a second request past the front end.

Affected software

CVE-2024-21647 is recorded against 1 package.

  • puma (fixed in 5.6.8)

Timeline and source

Published on 8 January 2024 and last revised on 17 June 2026. No public exploit is currently recorded for this entry. A vendor advisory or fix has been published. Record sourced from OSV.

References

github.com (Web)
nvd.nist.gov (Advisory)
github.com (Web)
github.com (Web)
github.com (Web)
github.com (Package)
github.com (Web)
lists.debian.org (Web)

Other advisories for this package

puma has other advisories on record. If you are patching this one, these are worth checking on the same host:

Same weakness in other software

These advisories are the same class of weakness (CWE-444: HTTP Request Smuggling) in other software:

CVE-2024-21647 on other distributions

Each distribution ships its own build and its own fixed version. Pick the one you run:

Details

Severity MEDIUM
CVSS Score 5.9
CVSS Vector CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:N/I:N/A:H
CWE CWE-444
Public Exploit ✅ No
Source OSV
Published 2024-01-08
Updated 2026-08-20
Modified 2026-06-17

Affected Packages

Software From version Fixed in
puma — 5.6.8

Similar Threats

Vulnerability Monitoring

Track new vulnerabilities in puma

CVE-2024-21647 is rated CVSS 5.9 Medium. BotEraser monitors your WordPress installation and notifies you when software you use appears in our vulnerability database.

Set Up Free Alerts →

No credit card required  ·  Results in minutes

ⓘ Data Notice: The information presented above has been compiled from publicly available internet sources. Boteraser aggregates this data solely for informational purposes and does not independently classify, evaluate, or endorse any findings about the vulnerabilities listed. The accuracy and completeness of this information is the sole responsibility of the original publishers. Boteraser and its operators accept no liability for any decisions made based on this data.

Browse related advisories

All advisoriesCVECVE 2024
✓