Netty: HTTP Header Injection via HttpProxyHandler Disabled Validation_CVE-2026-42578

2.9 / 10

LOW

CVSS:4.0/AV:N/AC:L/AT:P/PR:N/UI:N/VC:N/VI:L/VA:N/SC:N/SI:N/SA:N/E:P

Description

Netty is an asynchronous, event-driven network application framework. Prior to 4.2.13.Final and 4.1.133.Final, Netty's HttpProxyHandler constructs HTTP CONNECT requests with header validation explicitly disabled. The newInitialMessage() method creates headers using DefaultHttpHeadersFactory.headersFactory().withValidation(false), then adds user-provided outboundHeaders without any CRLF validation. This allows an attacker who can influence the outbound headers to inject arbitrary HTTP headers into the CONNECT request sent to the proxy server. This vulnerability is fixed in 4.2.13.Final and 4.1.133.Final.

Basic Information

ID CVE-2026-42578

Source GitHub_M

Published May 13, 2026 at 17:57

Modified May 13, 2026 at 18:37

Affected Product

Vendor netty

Product netty

Version >= 4.2.0.Alpha1, < 4.2.13.Final

Affected Versions netty netty >= 4.2.0.Alpha1, < 4.2.13.Final
netty netty < 4.1.133.Final

CWE Classification

CWE-113

References

github.com /netty/netty/security/advisories/GHSA-45q3-82m4-75jr

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    "published": "2026-05-13T17:57:43.538Z",
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