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Fencer Vulns
medium 6.8

CVE-2026-42586 json

Netty: CRLF Injection in Netty Redis Codec Encoder

published 2026-05-07 6 mo ago modified 2026-10-26 13 d ago also EUVD-2026-30129 , GHSA-rgrr-p7gp-5xj7

cvss
6.8
version 3.1, CNA
cisa kev
Not listed
not in CISA's catalog
epss
0.2%
EPSS 0.2% chance of exploitation in 30 days, percentile 12%
public exploits
0
none known

Summary

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.

Patch / fix

  • maven io.netty:netty-codec-redis 4.1.133.Final, 4.2.13.Final
  • io.netty netty-codec-redis 4.1.133.Final, 4.2.13.Final
  • netty netty 4.1.133.Final, 4.2.13.Final
  • netty Ubuntu Pro 18.04 LTS 1:4.1.7-4ubuntu0.1+esm6
  • netty Ubuntu Pro 20.04 LTS 1:4.1.45-1ubuntu0.1~esm6
  • netty Ubuntu Pro 22.04 LTS 1:4.1.48-4+deb11u2ubuntu0.1+esm3
  • netty Ubuntu Pro 24.04 LTS 1:4.1.48-9ubuntu0.1+esm3
  • netty Ubuntu Pro 26.04 LTS 1:4.1.48-16ubuntu0.1~esm2

ubuntu advisories UBUNTU-CVE-2026-42586

Ubuntu security data © Canonical Ltd., from https://github.com/canonical/ubuntu-security-notices via OSV; changed: normalised to fixed package versions per release. CC BY-SA 4.0

  • netty-tcnative SLES for SAP 15 SP6, SLES for SAP 15 SP5, SLES for SAP 15 SP4 +8 more 2.0.77-150200.3.39.1
  • netty SLE Module for Package Hub 15 SP7 4.1.133-150200.4.46.1

suse advisories SUSE-SU-2026:2308-1

  • netty openSUSE Tumbleweed 4.1.133-1.1

opensuse advisories openSUSE-SU-2026:10795-1

Vendor advisories

What the vendors themselves say about their products: affected, fixed or not affected, and what to do.

red hat product security vex CVE-2026-42586 updated cvss 6.8

netty-codec-redis: Netty: Command injection via CRLF characters in Redis codec encoder

  • Red Hat Fuse 7 netty-codec-redis
    affected: no fix planned “Out of support scope”
  • Red Hat Process Automation 7 netty-codec-redis Red Hat Single Sign-On 7 netty-codec-redis
    affected: no fix planned “Will not fix”
  • Red Hat build of Apache Camel 4.18.1.P1 for Spring Boot 3.5.16
    fixed: vendor fix RHSA-2026:37390
  • Red Hat Data Grid 8.6.2
    fixed: vendor fix RHSA-2026:41951
  • Red Hat JBoss Enterprise Application Platform 7 netty-codec-redis
    not affected: vulnerable code not in execute path
  • Red Hat JBoss Enterprise Application Platform Expansion Pack netty-codec-redis
    not affected: component not present

Red Hat CSAF VEX © Red Hat, Inc., from https://security.access.redhat.com/data/csaf/v2/vex/; changed: reduced to product statuses and remediations. CC BY 4.0 · csaf

CISA SSVC

Exploitation
none
Automatable
no
Technical impact
partial
Assessed
5 mo ago

Exploit prediction

0.22% chance of exploitation in the next 30 days, higher than 12% of all scored CVEs (FIRST EPSS, 2026-11-08).

Exploits and checks

  • github.com https://github.com/netty/netty/security/advisories/GHSA-rgrr-p7gp-5xj7 referenced PoC, tagged "exploit" by a source, unverified

CVSS scores

assigned by version score vector
CNA 3.1 6.8 CVSS:3.1/AV:L/AC:L/PR:N/UI:N/S:U/C:L/I:H/A:N
GitHub 3.1 6.8 CVSS:3.1/AV:L/AC:L/PR:N/UI:N/S:U/C:L/I:H/A:N
NVD 3.1 7.1 CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:N

Affected packages

ecosystem package affected fixed in
maven io.netty:netty-codec-redis
>=4.2.0.Alpha1, <4.2.13.Final
<4.1.133.Final
4.2.13.Final
4.1.133.Final

Affected products

  • netty netty
  • io.netty netty-codec-redis

Classification

Weakness
  • CWE-93 Improper Neutralization of CRLF Sequences

References

Sources

Fencer Vulns keeps one entry per vulnerability: the CVE id wins, then GHSA, and records that alias each other are merged, except that two CVEs always keep separate entries. The same data is available as JSON.

CPEs and fixed versions use Anchore's correction of NVD's data: Added CPE configurations because not yet analyzed by NVD.