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.
Affected products
| Vendor | Product | Affected | Fixed |
|---|---|---|---|
| netty | netty | >= 4.2.0.Alpha3, < 4.2.5.Final, <= 4.1.124.Final, < 4.1.125.Final | — |
Fixed in Linux distributions
Distributions backport fixes, so the version that fixes this vulnerability differs per release — upgrade to at least the version shown. From the distributions' security trackers and advisories.
Debian
Security tracker ↗| Release | Package | Fixed in | Advisory |
|---|---|---|---|
| Debian 14 | netty | 1:4.1.48-13 | — |
| Debian 13 | netty | 1:4.1.48-10+deb13u1 | DSA-6160-1 |
| Debian 12 | netty | 1:4.1.48-7+deb12u2 | DSA-6160-1 |
| Debian 11 | netty | 1:4.1.48-4+deb11u3 | DLA-4519-1 |
Ubuntu
Security tracker ↗| Release | Package | Fixed in | Advisory |
|---|---|---|---|
| Ubuntu 25.10 | netty | 1:4.1.48-10ubuntu0.25.10.2 | — |
| Ubuntu 24.04 LTS | netty | 1:4.1.48-9ubuntu0.1 | — |
| Ubuntu 22.04 LTS | netty | 1:4.1.48-4+deb11u2ubuntu0.1 | — |
| Ubuntu 18.04 LTS | netty-3.9 | No fix yet | — |
| Ubuntu 16.04 LTS | netty-3.9 | No fix yet | — |
Show 4 more (older releases, extended support, other products)Fewer releases
| Release | Package | Fixed in | Advisory |
|---|---|---|---|
| Ubuntu Pro 20.04 LTS | netty | 1:4.1.45-1ubuntu0.1~esm4 | — |
| Ubuntu Pro 18.04 LTS | netty | 1:4.1.7-4ubuntu0.1+esm5 | — |
| Ubuntu Pro 16.04 LTS | netty | 1:4.0.34-1ubuntu0.1~esm3 | — |
| Ubuntu Pro 14.04 LTS | netty | No fix yet | — |
Red Hat
Security tracker ↗| Release | Package | Fixed in | Advisory |
|---|---|---|---|
| Red Hat JBoss EAP 8 | eap8-apache-commons-lang | 3.18.0-1.redhat_00002.1.el8eap | RHSA-2025:17298 |
| Red Hat JBoss EAP 8 | eap8-apache-cxf +3 | 4.0.9-4.redhat_00002.1.el8eap | RHSA-2025:17317, RHSA-2025:17298 |
| Red Hat JBoss EAP 8 | eap8-cxf-xjc-dv +5 | 4.1.0-1.redhat_00001.1.el8eap | RHSA-2025:17317 |
| Red Hat JBoss EAP 8 | eap8-eap-product-conf-parent +1 | 800.9.1-3.GA_redhat_00004.1.el8eap | RHSA-2025:17317, RHSA-2025:17298 |
| Red Hat JBoss EAP 8 | eap8-jbossws-cxf | 7.3.4-1.Final_redhat_00001.1.el8eap | RHSA-2025:17317, RHSA-2025:17298 |
| Red Hat JBoss EAP 8 | eap8-netty +14 | 4.1.127-1.Final_redhat_00001.1.el8eap | RHSA-2025:17317, RHSA-2025:17298 |
| Red Hat JBoss EAP 8 | eap8-opensaml +13 | 4.3.2-2.redhat_00002.1.el8eap | RHSA-2025:17317, RHSA-2025:17298 |
| Red Hat JBoss EAP 8 | eap8-wildfly +4 | 8.0.9-8.GA_redhat_00008.1.el8eap | RHSA-2025:17317, RHSA-2025:17298 |
| Red Hat JBoss EAP 8 | eap8-wss4j +6 | 3.0.4-1.redhat_00002.1.el8eap | RHSA-2025:17317, RHSA-2025:17298 |
| Red Hat JBoss EAP 8 | eap8-xml-security | 3.0.5-1.redhat_00001.1.el8eap | RHSA-2025:17317, RHSA-2025:17298 |
SUSE
Security tracker ↗| Release | Package | Fixed in | Advisory |
|---|---|---|---|
| SLES 15 SP7 | netty | 4.1.126-150200.4.34.1 | SUSE-SU-2025:03114-1 |
| SLES 15 SP7 | netty-tcnative | 2.0.73-150200.3.30.1 | SUSE-SU-2025:03114-1 |
| SLES 15 SP6 | netty | 4.1.126-150200.4.34.1 | SUSE-SU-2025:03114-1 |
| SLES 15 SP6 | netty-tcnative | 2.0.73-150200.3.30.1 | SUSE-SU-2025:03114-1 |
| SLES 15 SP5 | netty-tcnative | 2.0.73-150200.3.30.1 | SUSE-SU-2025:03114-1 |
| SLES 15 SP4 | netty-tcnative | 2.0.73-150200.3.30.1 | SUSE-SU-2025:03114-1 |
| SLES 15 SP3 | netty-tcnative | 2.0.73-150200.3.30.1 | SUSE-SU-2025:03114-1 |
Show 7 more (older releases, extended support, other products)Fewer releases
| Release | Package | Fixed in | Advisory |
|---|---|---|---|
| SLES for SAP 15 SP5 | netty-tcnative | 2.0.73-150200.3.30.1 | SUSE-SU-2025:03114-1 |
| SLES for SAP 15 SP4 | netty-tcnative | 2.0.73-150200.3.30.1 | SUSE-SU-2025:03114-1 |
| SLES for SAP 15 SP3 | netty-tcnative | 2.0.73-150200.3.30.1 | SUSE-SU-2025:03114-1 |
| SLE HPC 15 SP5 | netty-tcnative | 2.0.73-150200.3.30.1 | SUSE-SU-2025:03114-1 |
| SLE HPC 15 SP4 | netty-tcnative | 2.0.73-150200.3.30.1 | SUSE-SU-2025:03114-1 |
| SLE HPC 15 SP3 | netty-tcnative | 2.0.73-150200.3.30.1 | SUSE-SU-2025:03114-1 |
| SUSE Enterprise Storage 7.1 | netty-tcnative | 2.0.73-150200.3.30.1 | SUSE-SU-2025:03114-1 |
openSUSE
Security tracker ↗| Release | Package | Fixed in | Advisory |
|---|---|---|---|
| openSUSE Tumbleweed | netty | 4.1.126-1.1 | openSUSE-SU-2025:15520-1 |
| openSUSE Leap 15.6 | netty | 4.1.126-150200.4.34.1 | SUSE-SU-2025:03114-1 |
| openSUSE Leap 15.6 | netty-tcnative | 2.0.73-150200.3.30.1 | SUSE-SU-2025:03114-1 |
Wolfi
| Release | Package | Fixed in | Advisory |
|---|---|---|---|
| Wolfi rolling | akhq | 0.26.0-r4 | — |
| Wolfi rolling | apache-activemq-artemis +1 | 2.42.0-r8 | — |
| Wolfi rolling | apache-nifi +2 | 2.5.0-r7 | — |
| Wolfi rolling | apicurio-registry +2 | 3.0.14-r1 | — |
| Wolfi rolling | celeborn-0.6 | 0.6.3-r7 | — |
| Wolfi rolling | docker-selenium +18 | 4.35.0.20250828-r0 | — |
| Wolfi rolling | druid +1 | 34.0.0-r4 | — |
| Wolfi rolling | flyway | 11.12.0-r1 | — |
| Wolfi rolling | kafka-strimzi-compat +12 | 0.47.0-r7 | — |
| Wolfi rolling | kserve-modelmesh +1 | 0.12.0-r16 | — |
| Wolfi rolling | opensearch-2 | 2.19.4-r0 | — |
| Wolfi rolling | selenium-server | 4.38.0-r0 | — |
| Wolfi rolling | sonarqube | 25.12.0.117093-r1 | — |
| Wolfi rolling | tez | 0.10.5-r5 | — |
| Wolfi rolling | thingsboard +4 | 4.2-r4 | — |
| Wolfi rolling | trino +58 | 476-r8 | — |
| Wolfi rolling | wavefront-proxy +3 | 13.8-r3 | — |
| Wolfi rolling | wildfly +4 | 37.0.1-r1 | — |
| Wolfi rolling | zipkin +2 | 3.5.1-r5 | — |
Affected packages
| Ecosystem | Package | Affected | Fixed | Record |
|---|---|---|---|---|
| Maven | io.netty:netty-codec-http | < 4.1.125.Final | 4.1.125.Final | GHSA-fghv-69vj-qj49 |
| Maven | io.netty:netty-codec-http | >= 4.2.0.Alpha1, < 4.2.5.Final | 4.2.5.Final | GHSA-fghv-69vj-qj49 |
Advisories 11
- WID-SEC-2026-3046 IBM Concert: Mehrere Schwachstellen BSI CERT-Bund (WID) · Nov 10, 2026
- WID-SEC-2025-2301 Red Hat Enterprise Linux: Mehrere Schwachstellen BSI CERT-Bund (WID) · Nov 3, 2026
- RHSA-2025:17317 Red Hat Security Advisory: Red Hat JBoss Enterprise Application Platform 8.0.9 security update Red Hat Security Advisories (RHSA) · Oct 20, 2026
- RHSA-2025:17298 Red Hat Security Advisory: Red Hat JBoss Enterprise Application Platform 8.1.0 security update Red Hat Security Advisories (RHSA) · Oct 20, 2026
- WID-SEC-2025-2098 IBM SPSS: Mehrere Schwachstellen BSI CERT-Bund (WID) · Oct 15, 2026
- DLA-4519-1 netty - security update Debian Security (DSA / DLA) · Mar 31, 2026
- DSA-6160-1 netty - security update Debian Security (DSA / DLA) · Mar 23, 2026
- openSUSE-SU-2025:15520-1 netty-4.1.126-1.1 on GA media SUSE / openSUSE Security Updates · Mar 23, 2026
- SUSE-SU-2025:03114-1 Security update for netty, netty-tcnative SUSE / openSUSE Security Updates · Feb 4, 2026
- WID-SEC-2026-0277 NetApp ActiveIQ Unified Manager (Apache Netty): Mehrere Schwachstellen BSI CERT-Bund (WID) · Feb 1, 2026
- WID-SEC-2025-2763 IBM InfoSphere Information Server (Netty, FreeScout): Mehrere Schwachstellen BSI CERT-Bund (WID) · Dec 8, 2025
References
- https://github.com/netty/netty/security/advisories/GHSA-fghv-69vj-qj49
- https://github.com/JLLeitschuh/unCVEed/issues/1
- https://github.com/netty/netty/issues/15522
- https://github.com/netty/netty/pull/15611
- https://github.com/netty/netty/commit/edb55fd8e0a3bcbd85881e423464f585183d1284
- https://datatracker.ietf.org/doc/html/rfc9112#name-chunked-transfer-coding
- https://w4ke.info/2025/06/18/funky-chunks.html