Puma up to 7.2.0/8.0.1 PROXY Protocol buffer overflow

CVSS Meta Temp Score
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Current Exploit Price (≈)
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CTI Interest Score
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5.1$0-$5k0.68

Summaryinfo

A vulnerability described as problematic has been identified in Puma up to 7.2.0/8.0.1. Affected by this issue is some unknown functionality of the component PROXY Protocol. Executing a manipulation can lead to buffer overflow. This vulnerability is handled as CVE-2026-47736. The attack can be executed remotely. There is not any exploit available.

Detailsinfo

A vulnerability was found in Puma up to 7.2.0/8.0.1. It has been declared as problematic. This vulnerability affects an unknown code block of the component PROXY Protocol. The manipulation with an unknown input leads to a buffer overflow vulnerability. The CWE definition for the vulnerability is CWE-120. The product copies an input buffer to an output buffer without verifying that the size of the input buffer is less than the size of the output buffer, leading to a buffer overflow. As an impact it is known to affect availability. CVE summarizes:

Puma is a Ruby/Rack web server built for parallelism. From 5.5.0 until 7.2.1 and 8.0.2, when PROXY protocol v1 support is enabled, Puma reads incoming bytes into an internal buffer while waiting for CRLF to determine whether a PROXY v1 line is present, allowing an attacker that continuously sends bytes without CRLF to cause unbounded in-process memory growth and additional CPU cost from repeatedly scanning the growing buffer. This issue is fixed in versions 7.2.1 and 8.0.2.

The advisory is available at github.com. This vulnerability was named CVE-2026-47736 since 05/20/2026. The exploitation appears to be easy. The attack can be initiated remotely. No form of authentication is required for a successful exploitation. The technical details are unknown and an exploit is not available.

Upgrading to version 7.2.1 or 8.0.2 eliminates this vulnerability.

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Productinfo

Name

Version

Website

CPE 2.3info

CPE 2.2info

CVSSv4info

VulDB Vector: 🔒
VulDB Reliability: 🔍

CVSSv3info

VulDB Meta Base Score: 5.3
VulDB Meta Temp Score: 5.1

VulDB Base Score: 5.3
VulDB Temp Score: 5.1
VulDB Vector: 🔒
VulDB Reliability: 🔍

CVSSv2info

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VulDB Base Score: 🔒
VulDB Temp Score: 🔒
VulDB Reliability: 🔍

Exploitinginfo

Class: Buffer overflow
CWE: CWE-120 / CWE-119
CAPEC: 🔒
ATT&CK: 🔒

Physical: No
Local: No
Remote: Yes

Availability: 🔒
Status: Not defined
Price Prediction: 🔍
Current Price Estimation: 🔒

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Threat Intelligenceinfo

Interest: 🔍
Active Actors: 🔍
Active APT Groups: 🔍

Countermeasuresinfo

Recommended: no mitigation known
Status: 🔍

0-Day Time: 🔒

Upgrade: Puma 7.2.1/8.0.2

Timelineinfo

05/20/2026 CVE reserved
07/14/2026 +55 days VulDB entry created
07/15/2026 +0 days Advisory disclosed
07/15/2026 +0 days VulDB entry last update

Sourcesinfo

Product: github.com

Advisory: github.com
Status: Confirmed

CVE: CVE-2026-47736 (🔒)
GCVE (CVE): GCVE-0-2026-47736
GCVE (VulDB): GCVE-100-379006

Entryinfo

Created: 07/15/2026 01:32
Changes: 07/15/2026 01:32 (52)
Complete: 🔍
Cache ID: 216::103

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