CVE-2026-42586: Netty

High severity, CVSS 7.1. EPSS: 0.2% chance of exploitation in the next 30 days.

Netty is an asynchronous, event-driven network application framework. Prior to 4.2.13.Final and 4.1.133.Final, the Netty Redis codec encoder (RedisEncoder) writes user-controlled string content directly to the network output buffer without validating or sanitizing CRLF (\r\n) characters. Since the Redis Serialization Protocol (RESP) uses CRLF as the command/response delimiter, an attacker who can control the content of a Redis message can inject arbitrary Redis commands or forge fake responses. This vulnerability is fixed in 4.2.13.Final and 4.1.133.Final.

Affected products

• Netty Netty: before 4.1.133 (fixed in 4.1.133); from 4.2.0, before 4.2.13 (fixed in 4.2.13)

Published 2026-05-13. Last modified 2026-06-17.