CVE-2025-67735
Medium
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.
SeverityMedium
CVSS6.5
Exploit probability—
ProductNetty
PublishedDec 16, 2025
First seenDec 16, 2025
Weakness typeCWE-93CWE-93
How to fix
Update
- netty netty4.1.129, 4.2.8 or later
- io.netty:netty-codec-http4.2.8.Final, 4.1.129.Final or later
Affected products
| Product | Affected versions | Fixed in |
|---|---|---|
| netty netty | v < 4.1.129, 4.2.0 ≤ v < 4.2.8 | 4.1.129, 4.2.8 |
| io.netty:netty-codec-httpMaven | 4.2.0.Alpha1 ≤ v < 4.2.8.Final, v < 4.1.129.Final | 4.2.8.Final, 4.1.129.Final |
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