Description
Netty is an asynchronous, event-driven network application framework. Prior to versions 4.1.136.Final and 4.2.16.Final, ab attacker can force WebSocket upgrade via the lax V07 (or V08) handshaker by sending `Sec-WebSocket-Version: 7` and omitting `Connection: Upgrade` / `Upgrade: websocket` headers, completing a protocol switch that a proxy would not recognize as an Upgrade request and enabling HTTP request smuggling / protocol-confusion attacks. This issue has been fixed in versions 4.1.136.Final and 4.2.16.Final.
Affected products
| Vendor | Product | Affected | Fixed |
|---|---|---|---|
| netty | netty | >=4.2.0.Final, < 4.2.16.Final, < 4.1.136.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 | No fix yet | — |
| Debian 13 | netty | No fix yet | — |
| Debian 12 | netty | No fix yet | — |
Ubuntu
Security tracker ↗| Release | Package | Fixed in | Advisory |
|---|---|---|---|
| Ubuntu 26.10 | netty | No fix yet | — |
Show 7 more (older releases, extended support, other products)Fewer releases
| Release | Package | Fixed in | Advisory |
|---|---|---|---|
| Ubuntu Pro 26.04 LTS | netty | No fix yet | — |
| Ubuntu Pro 24.04 LTS | netty | No fix yet | — |
| Ubuntu Pro 22.04 LTS | netty | No fix yet | — |
| Ubuntu Pro 20.04 LTS | netty | No fix yet | — |
| Ubuntu Pro 18.04 LTS | netty | No fix yet | — |
| Ubuntu Pro 16.04 LTS | netty | No fix yet | — |
| Ubuntu Pro 14.04 LTS | netty | No fix yet | — |
SUSE
Security tracker ↗| Release | Package | Fixed in | Advisory |
|---|---|---|---|
| SLES 15 SP7 | netty | 4.1.136-150200.4.53.1 | SUSE-SU-2026:3482-1 |
| SLES 15 SP7 | netty-tcnative | 2.0.80-150200.3.48.1 | SUSE-SU-2026:3482-1 |
| SLES 15 SP6 | netty-tcnative | 2.0.80-150200.3.48.1 | SUSE-SU-2026:3482-1 |
| SLES 15 SP5 | netty-tcnative | 2.0.80-150200.3.48.1 | SUSE-SU-2026:3482-1 |
| SLES 15 SP4 | netty-tcnative | 2.0.80-150200.3.48.1 | SUSE-SU-2026:3482-1 |
Show 5 more (older releases, extended support, other products)Fewer releases
| Release | Package | Fixed in | Advisory |
|---|---|---|---|
| SLES for SAP 15 SP6 | netty-tcnative | 2.0.80-150200.3.48.1 | SUSE-SU-2026:3482-1 |
| SLES for SAP 15 SP5 | netty-tcnative | 2.0.80-150200.3.48.1 | SUSE-SU-2026:3482-1 |
| SLES for SAP 15 SP4 | netty-tcnative | 2.0.80-150200.3.48.1 | SUSE-SU-2026:3482-1 |
| SLE HPC 15 SP5 | netty-tcnative | 2.0.80-150200.3.48.1 | SUSE-SU-2026:3482-1 |
| SLE HPC 15 SP4 | netty-tcnative | 2.0.80-150200.3.48.1 | SUSE-SU-2026:3482-1 |
openSUSE
Security tracker ↗| Release | Package | Fixed in | Advisory |
|---|---|---|---|
| openSUSE Tumbleweed | netty | 4.1.136-1.1 | openSUSE-SU-2026:11394-1 |
Wolfi
| Release | Package | Fixed in | Advisory |
|---|---|---|---|
| Wolfi rolling | akhq | 0.27.1-r12 | — |
| Wolfi rolling | apache-activemq-artemis | 2.55.0-r1 | — |
| Wolfi rolling | apache-nifi | 2.10.0-r6 | — |
| Wolfi rolling | apache-pulsar-4.2 | 4.2.3-r3 | — |
| Wolfi rolling | apicurio-registry | 3.3.0-r11 | — |
| Wolfi rolling | celeborn-0.6 | 0.6.3-r13 | — |
| Wolfi rolling | cloudwatch-exporter | 0.18.0-r1 | — |
| Wolfi rolling | druid | 37.0.0-r45 | — |
| Wolfi rolling | flyway | 13.0.0-r1 | — |
| Wolfi rolling | infinispan-16.1 | 16.1.4-r7 | — |
| Wolfi rolling | infinispan-16.2 | 16.2.1-r2 | — |
| Wolfi rolling | keycloak-26.6 +2 | 26.6.4-r24 | — |
| Wolfi rolling | kserve-modelmesh | 0.12.0-r38 | — |
| Wolfi rolling | logstash-9.3 +5 | No fix yet | — |
| Wolfi rolling | logstash-9.4 +1 | 9.4.4-r3 | — |
| Wolfi rolling | management-api-for-apache-cassandra-5.0 | 0.1.122-r2 | — |
| Wolfi rolling | neo4j-2026.05 +1 | 2026.05.0-r12 | — |
| Wolfi rolling | neo4j-2026.06 | 2026.06.0-r4 | — |
| Wolfi rolling | opensearch-2 | 2.19.6-r6 | — |
| Wolfi rolling | opensearch-3 +6 | 3.7.0-r5 | — |
| Wolfi rolling | opensearch-3-discovery-ec2 +2 | 3.8.0-r3 | — |
| Wolfi rolling | opensearch-3-security-analytics | 3.8.0-r2 | — |
| Wolfi rolling | spark-4.0-scala-2.13 | 4.0.4-r1 | — |
| Wolfi rolling | spark-4.1-scala-2.13 | 4.1.3-r2 | — |
| Wolfi rolling | strimzi-kafka-operator-kafka-init +6 | 1.1.0-r4 | — |
| Wolfi rolling | tez | 0.10.5-r24 | — |
| Wolfi rolling | thingsboard-tb-node +1 | 4.3.1.3-r9 | — |
| Wolfi rolling | trino-plugin-opensearch | 483-r7 | — |
| Wolfi rolling | wavefront-proxy | 13.9-r24 | — |
| Wolfi rolling | zipkin +1 | 3.6.1-r19 | — |
Affected packages
| Ecosystem | Package | Affected | Fixed | Record |
|---|---|---|---|---|
| Maven | io.netty:netty-codec-http | >= 4.2.0.Final, < 4.2.16.Final | 4.2.16.Final | GHSA-4mp9-239f-g9hg |
| Maven | io.netty:netty-codec-http | < 4.1.136.Final | 4.1.136.Final | GHSA-4mp9-239f-g9hg |
Advisories 4
- WID-SEC-2026-2356 Netty: Mehrere Schwachstellen BSI CERT-Bund (WID) · Oct 25, 2026
- SCA-2026-0013 Vulnerabilities Affecting SICK CorivaEngine SICK PSIRT · Sep 11, 2026
- SUSE-SU-2026:3482-1 Security update for netty, netty-tcnative SUSE / openSUSE Security Updates · Aug 5, 2026
- openSUSE-SU-2026:11394-1 netty-4.1.136-1.1 on GA media SUSE / openSUSE Security Updates · Jul 29, 2026