CVE-2025-67735

Netty is an asynchronous, event-driven network application framework. In versions prior to 4.1.129.Final and 4.2.8.Final, the `io.netty.handler.codec.http.HttpRequestEncoder` has a CRLF injection with the request URI when constructing a request. This leads to request smuggling when `HttpRequestEncoder` is used without proper sanitization of the URI. Any application / framework using `HttpRequestEncoder` can be subject to be abused to perform request smuggling using CRLF injection. Versions 4.1.129.Final and 4.2.8.Final fix the issue.

CVSS v3 6.5 MEDIUM

6.5^/10

CVSS v3 : MEDIUM

Vector :

Exploitability : 3.9 / Impact : 2.5

Attack Vector NETWORK

Attack Complexity LOW

Privileges Required NONE

User Interaction NONE

Confidentiality Impact LOW

Integrity Impact LOW

Availability Impact NONE

Scope UNCHANGED

References

Link	Resource
https://github.com/netty/netty/security/advisories/GHSA-84h7-rjj3-6jx4	Exploit Vendor Advisory

Configurations

Configuration 1 (hide)

OR	cpe:2.3:a:netty:netty::::::::
	cpe:2.3:a:netty:netty::::::::

History

14 Oct 2026, 13:10

Type	Values Removed	Values Added
Summary		(es) Netty es un framework de aplicación de red asíncrono y basado en eventos. En versiones anteriores a 4.1.129.Final y 4.2.8.Final, el 'io.netty.handler.codec.http.HttpRequestEncoder' tiene una inyección CRLF con la URI de la solicitud al construir una solicitud. Esto lleva a la suplantación de solicitudes (request smuggling) cuando se utiliza 'HttpRequestEncoder' sin una sanitización adecuada de la URI. Cualquier aplicación / framework que utilice 'HttpRequestEncoder' puede ser susceptible de ser abusada para realizar suplantación de solicitudes (request smuggling) utilizando inyección CRLF. Las versiones 4.1.129.Final y 4.2.8.Final corrigen el problema.

Information

Published : 2025-12-16 01:15

Updated : 2026-10-14 13:10

NVD link : CVE-2025-67735

Mitre link : CVE-2025-67735

CVE.ORG link : CVE-2025-67735

JSON object : View

Products Affected

netty

netty

CWE

CWE-93

Improper Neutralization of CRLF Sequences ('CRLF Injection')

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