VULNERABILITY INTELLIGENCE

CVE-2026-47736

CVSS score7.5 HIGH
EPSS probability0.35%
CISA KEVNot currently listed
Published2026-07-14
Last modified2026-07-15
CVSS vectorCVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H

Description

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.

Weakness classification

  • security-advisories@github.com: CWE-400

Primary references