CVE-2025-67735

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.

CVSS Metrics

• v3.1•MEDIUM•Score: 6.5CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:L/I:L/A:N

EPSS Trends

Current EPSS score: 0.02%• Percentile: 7%

Techniques & Countermeasures

• CWE-93•Improper Neutralization of CRLF Sequences ('CRLF Injection')

  The product uses CRLF (carriage return line feeds) as a special element, e.g. to separate lines or records, but it does not neutralize or incorrectly neutralizes CRLF sequences from inputs.

Affected Systems

• io.netty•netty-codec-http

  ≥ 4.2.0.Alpha1, < 4.2.8.Final | < 4.1.129.Final

• netty•netty

  ≥ 4.2.0.Alpha1, < 4.2.8.Final | < 4.1.129.Final | < 4.1.129 | ≥ 4.2.0, < 4.2.8

References (4)

• https://github.com/netty/netty/security/advisories/GHSA-84h7-rjj3-6jx4
• https://nvd.nist.gov/vuln/detail/CVE-2025-67735
• https://github.com/netty/netty/commit/77e81f1e5944d98b3acf887d3aa443b252752e94
• https://github.com/netty/netty