Find real vulnerabilities before they ship
Netty is an asynchronous, event-driven network application framework. Prior to 4.2.13.Final and 4.1.133.Final, HttpObjectDecoder strips a conflicting Content-Length header when a request carries both Transfer-Encoding: chunked and Content-Length, but only for HTTP/1.1 messages. The guard is absent for HTTP/1.0. An attacker that sends an HTTP/1.0 request with both headers causes Netty to decode the body as chunked while leaving Content-Length intact in the forwarded HttpMessage. Any downstream proxy or handler that trusts Content-Length over Transfer-Encoding will disagree on message boundaries, enabling request smuggling. This vulnerability is fixed in 4.2.13.Final and 4.1.133.Final.
Base Score
9.8| Package (Ecosystem) | Introduced | Fixed | Limit |
|---|---|---|---|
| io.netty:netty-codec-http(Maven) | 4.2.0.Alpha1 | 4.2.13.Final | N/A |
| io.netty:netty-codec-http(Maven) | 0 | 4.1.133.Final | N/A |
| Base Score | 9.8 |
|---|---|
| Vector String | CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H |
| Base Severity | Critical |
| Version | 3.1 |
| Attack Vector (AV) | NETWORK |
