CVE-2025-6442 MEDIUM

CVE-2025-6442: Ruby WEBrick read_header HTTP Request Smuggling Vulnerability

Vendor Ruby
Product WEBrick
Weakness CWE-444
Published June 25, 2025
Last update June 25, 2025
View on NVD All CVEs

CVSS base score

6.5/10
Attack vector Network
Attack complexity High
Privileges required None
User interaction None
Confidentiality Low
Integrity High

CVSS vector

CVSS:3.0/AV:N/AC:H/PR:N/UI:N/S:U/C:L/I:H/A:N

What the vulnerability does

01Description

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.

Key dates

02Disclosure timeline

June 25, 2025 CVE published
June 25, 2025 Record updated