CVE-2025-67735
MEDIUM6.5EPSS 0.02%Netty has a CRLF Injection vulnerability in io.netty.handler.codec.http.HttpRequestEncoder
Published: 12/15/2025Modified: 4/28/2026
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.
Affected packages (2)
- Debian/nettyfrom 0, < 1:4.1.48-4+deb11u3
- Maven/io.netty:netty-codec-http>= 4.2.0.Alpha1, < 4.2.8.Final
CVSS scores
| Source | Version | Severity | Vector |
|---|---|---|---|
| osv | CVSS 3.1 | MEDIUM6.5 | CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:L/I:L/A:N |
References (5)
- ADVISORYhttps://nvd.nist.gov/vuln/detail/CVE-2025-67735
- ADVISORYhttps://security-tracker.debian.org/tracker/CVE-2025-67735
- PATCHhttps://github.com/netty/netty
- WEBhttps://github.com/netty/netty/commit/77e81f1e5944d98b3acf887d3aa443b252752e94
- WEBhttps://github.com/netty/netty/security/advisories/GHSA-84h7-rjj3-6jx4