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National Vulnerability Database

National Vulnerability Database

NVD

National Vulnerability Database
  1. Vulnerabilities

CVE-2025-6442 Detail

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.


Metrics

 
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CVSS 4.0 Severity and Vector Strings:

NIST CVSS score
NIST: NVD
N/A
NVD assessment not yet provided.

References to Advisories, Solutions, and Tools

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URL Source(s) Tag(s)
https://github.com/ruby/webrick/commit/ee60354bcb84ec33b9245e1d1aa6e1f7e8132101#diff-ad02984d873efb089aa51551bc6b7d307a53e0ba1ac439e91d69c2e58a478864 Zero Day Initiative Patch 
https://www.zerodayinitiative.com/advisories/ZDI-25-414/ Zero Day Initiative Third Party Advisory 

Weakness Enumeration

CWE-ID CWE Name Source
CWE-444 Inconsistent Interpretation of HTTP Requests ('HTTP Request/Response Smuggling') Zero Day Initiative  

Known Affected Software Configurations Switch to CPE 2.2

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Change History

2 change records found show changes

Quick Info

CVE Dictionary Entry:
CVE-2025-6442
NVD Published Date:
06/25/2025
NVD Last Modified:
08/18/2025
Source:
Zero Day Initiative