CVE-2026-42586
Netty Redis Codec Encoder has a CRLF Injection Issue
Description
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.
How to fix CVE-2026-42586
To remediate CVE-2026-42586, upgrade the affected package to a fixed version below.
- —no fix listed
- —upgrade to 4.2.13.Final or later
Is CVE-2026-42586 being exploited?
Low — EPSS is 0.0%, meaning exploitation activity has not been observed at scale.
Affected packages (2)
- from 0
- >= 4.2.0.Alpha1, < 4.2.13.Final
CVSS scores
| Source | Version | Severity | Vector |
|---|---|---|---|
| osv | CVSS 3.1 | MEDIUM6.8 | CVSS:3.1/AV:L/AC:L/PR:N/UI:N/S:U/C:L/I:H/A:N |