CVE-2025-67735

MEDIUM

Netty <4.1.129.Final, <4.2.8.Final - Request Smuggling

Title source: llm
STIX 2.1

Description

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.

References (1)

Core 1
Core References
Exploit, Vendor Advisory x_refsource_confirm
https://github.com/netty/netty/security/advisories/GHSA-84h7-rjj3-6jx4

Scores

CVSS v3 6.5
EPSS 0.0029
EPSS Percentile 20.7%
Attack Vector NETWORK
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:L/I:L/A:N

CISA SSVC

Vulnrichment
Exploitation poc
Automatable yes
Technical Impact partial

Details

CWE
CWE-93
Status published
Products (2)
io.netty/netty-codec-http 4.2.0.Alpha1 - 4.2.8.FinalMaven
netty/netty < 4.1.129
Published Dec 16, 2025
Tracked Since Feb 18, 2026