Rapid7

vulnerability

Red Hat: CVE-2025-6442: webrick: Ruby WEBrick Request Smuggling Vulnerability

Severity
8
CVSS
(AV:N/AC:M/Au:N/C:P/I:C/A:N)
Published
Jun 25, 2025
Added
Jul 9, 2025
Modified
Jul 10, 2025

Description

Ruby WEBrick read_header HTTP Request Smuggling Vulnerability. This vulnerability allows remote attackers to smuggle arbitrary HTTP requests on affected installations of Ruby WEBrick. This issue is exploitable when the product is deployed behind an HTTP proxy that fulfills specific conditions.

The specific flaw exists within the read_headers method. The issue results from the inconsistent parsing of terminators of HTTP headers. An attacker can leverage this vulnerability to smuggle arbitrary HTTP requests. Was ZDI-CAN-21876.

Solution

no-fix-redhat-rpm-package
Title
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