CVE-2025-58056
Severity CVSS v4.0:
LOW
Type:
Unavailable / Other
Publication date:
03/09/2025
Last modified:
08/09/2025
Description
Netty is an asynchronous event-driven network application framework for development of maintainable high performance protocol servers and clients. In versions 4.1.124.Final, and 4.2.0.Alpha3 through 4.2.4.Final, Netty incorrectly accepts standalone newline characters (LF) as a chunk-size line terminator, regardless of a preceding carriage return (CR), instead of requiring CRLF per HTTP/1.1 standards. When combined with reverse proxies that parse LF differently (treating it as part of the chunk extension), attackers can craft requests that the proxy sees as one request but Netty processes as two, enabling request smuggling attacks. This is fixed in versions 4.1.125.Final and 4.2.5.Final.
Impact
Base Score 4.0
2.90
Severity 4.0
LOW
Base Score 3.x
7.50
Severity 3.x
HIGH
Vulnerable products and versions
| CPE | From | Up to |
|---|---|---|
| cpe:2.3:a:netty:netty:*:*:*:*:*:*:*:* | 4.1.125 (excluding) | |
| cpe:2.3:a:netty:netty:*:*:*:*:*:*:*:* | 4.2.0 (including) | 4.2.5 (excluding) |
To consult the complete list of CPE names with products and versions, see this page
References to Advisories, Solutions, and Tools
- https://datatracker.ietf.org/doc/html/rfc9112#name-chunked-transfer-coding
- https://github.com/JLLeitschuh/unCVEed/issues/1
- https://github.com/netty/netty/commit/edb55fd8e0a3bcbd85881e423464f585183d1284
- https://github.com/netty/netty/issues/15522
- https://github.com/netty/netty/pull/15611
- https://github.com/netty/netty/security/advisories/GHSA-fghv-69vj-qj49
- https://w4ke.info/2025/06/18/funky-chunks.html



