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.
Exploitability
AV:NAC:LPR:NUI:NScope
S:UImpact
C:LI:LA:N6.5/CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:L/I:L/A:NOther