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.
Metrics
CVSS 3.1 6.5/10
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:L/I:L/A:NWeakness enumeration
Affected software
| Vendor | Product | Versions |
|---|---|---|
| netty | netty | >= 4.2.0.Alpha1, < 4.2.8.Final; < 4.1.129.Final |
References
- https://github.com/netty/netty/security/advisories/GHSA-84h7-rjj3-6jx4Exploit, Vendor Advisory
Timeline
- Published
- Dec 16, 2025
- Last modified
- Oct 14, 2026
- NVD status
- Analyzed