CVE-2026-55851
Fixed in a distro release EPSS <1%CVSS 8.7
Netty is a network application framework for development of protocol servers and clients. In versions 4.2.0.Final up to (but not including) 4.2.16.Final, and 4.1.0.Final up to (but not including) 4.1.135, the `HAProxyMessageDecoder` in Netty's `codec-haproxy` module performs protocol version detection by reading the 13th byte as a signed Java `byte` and widening it to `int` without masking; a PROXY protocol v2 binary prefix followed by version byte `0xFF` sign-extends to `-1`, collides with the decoder's need-more-data sentinel, and causes `ByteToMessageDecoder` to accumulate inbound bytes in an unbounded `cumulation` buffer until direct memory is exhausted. This issue is fixed in versions 4.1.136.Final and 4.2.16.Final.
Products: netty
Fixed upstream
| Ecosystem | Package | Fixed in |
|---|---|---|
| Maven | io.netty:netty-codec-haproxy | 4.2.16.Final |
| Maven | io.netty:netty-codec-haproxy | 4.1.136.Final |
Distro releases
| Release | Package | Fixed in |
|---|---|---|
| Chainguard | apache-activemq-artemis | 2.55.0-r1 |
| Chainguard | apache-hop | 2.18.1-r12 |
| Chainguard | apache-hop-fips | 2.18.1-r6 |
| Chainguard | apache-pulsar-4.0 | 4.0.12-r2 |
| Chainguard | apache-pulsar-4.1 | 4.1.3-r15 |
| Chainguard | apache-pulsar-4.2 | 4.2.3-r3 |
| Chainguard | apache-pulsar-fips-4.0 | 4.0.12-r2 |
| Chainguard | apache-pulsar-fips-4.1 | no fix |
| Chainguard | apache-pulsar-fips-4.2 | 4.2.3-r2 |
| Chainguard | apicurio-registry | 3.3.0-r11 |
| Chainguard | apicurio-registry-3-operator | 3.3.0-r11 |
| Chainguard | apicurio-registry-3-operator-fips | 3.3.0-r8 |
| Chainguard | apicurio-registry-fips | 3.3.0-r8 |
| Chainguard | celeborn-0.5 | 0.5.4-r31 |
| Chainguard | celeborn-0.6 | 0.6.3-r12 |
| Chainguard | floci | 1.5.33-r5 |
| Chainguard | floci-az | 0.9.0-r3 |
| Chainguard | gremlin-server | 3.8.1-r2 |
| Chainguard | hadoop-3.5 | no fix |
| Chainguard | hadoop-fips-3.3.6 | no fix |
| Chainguard | hadoop-fips-3.4.2 | no fix |
| Chainguard | hadoop-fips-3.5 | 3.5.0-r3 |
| Chainguard | hadoop-fips-3.5 | no fix |
| Chainguard | hono-adapter-mqtt | 2.7.0-r30 |
| Chainguard | hono-cli | 2.7.0-r31 |
| Chainguard | hono-cli | 2.7.0-r30 |
| Chainguard | hono-service-auth | 2.7.0-r30 |
| Chainguard | hono-service-command-router | 2.7.0-r31 |
| Chainguard | hono-service-command-router | 2.7.0-r30 |
| Chainguard | hono-service-device-registry-jdbc | 2.7.0-r31 |
| Chainguard | hono-service-device-registry-jdbc | 2.7.0-r30 |
| Chainguard | keycloak-26.5 | no fix |
| Chainguard | keycloak-26.5-iamguarded-compat | no fix |
| Chainguard | keycloak-26.5-operator | no fix |
| Chainguard | keycloak-26.6 | 26.6.6-r0 |
| Chainguard | keycloak-26.6-iamguarded-compat | 26.6.6-r0 |
| Chainguard | keycloak-26.6-operator | 26.6.6-r0 |
| Chainguard | keycloak-26.7 | 26.7.0-r5 |
| Chainguard | keycloak-26.7-iamguarded-compat | 26.7.0-r5 |
| Chainguard | keycloak-26.7-operator | 26.7.0-r5 |
| Chainguard | keycloak-fips-26.5 | no fix |
| Chainguard | keycloak-fips-26.5-iamguarded-fips | no fix |
| Chainguard | keycloak-fips-26.5-operator | no fix |
| Chainguard | keycloak-fips-26.6 | 26.6.6-r0 |
| Chainguard | keycloak-fips-26.6-iamguarded-fips | 26.6.6-r0 |
| Chainguard | keycloak-fips-26.6-operator | 26.6.6-r0 |
| Chainguard | keycloak-fips-26.7 | 26.7.0-r5 |
| Chainguard | keycloak-fips-26.7 | 26.7.0-r4 |
| Chainguard | keycloak-fips-26.7-iamguarded-fips | 26.7.0-r4 |
| Chainguard | keycloak-fips-26.7-iamguarded-fips | 26.7.0-r5 |
| Chainguard | keycloak-fips-26.7-operator | 26.7.0-r4 |
| Chainguard | keycloak-fips-26.7-operator | 26.7.0-r5 |
| Chainguard | knative-kafka-broker-1.20-dispatcher-loom | no fix |
| Chainguard | knative-kafka-broker-1.20-receiver-loom | no fix |
| Chainguard | knative-kafka-broker-1.21-dispatcher-loom | 1.21.4-r14 |
| Chainguard | knative-kafka-broker-1.21-receiver-loom | 1.21.4-r14 |
| Chainguard | knative-kafka-broker-1.22-dispatcher-loom | 1.22.3-r2 |
| Chainguard | knative-kafka-broker-1.22-receiver-loom | 1.22.3-r2 |
| Chainguard | knative-kafka-broker-fips-1.20-dispatcher-loom | no fix |
| Chainguard | knative-kafka-broker-fips-1.20-receiver-loom | no fix |
| Chainguard | knative-kafka-broker-fips-1.21-dispatcher-loom | 1.21.4-r9 |
| Chainguard | knative-kafka-broker-fips-1.21-receiver-loom | 1.21.4-r9 |
| Chainguard | knative-kafka-broker-fips-1.22-dispatcher-loom | 1.22.2-r12 |
| Chainguard | knative-kafka-broker-fips-1.22-receiver-loom | 1.22.2-r12 |
| Chainguard | management-api-for-apache-cassandra-5.0 | 0.1.122-r2 |
| Chainguard | neo4j-2026.04 | 2026.04.0-r3 |
| Chainguard | neo4j-2026.05 | 2026.05.0-r12 |
| Chainguard | neo4j-2026.05-docker-publish | no fix |
| Chainguard | neo4j-2026.06 | 2026.06.0-r4 |
| Chainguard | pinot | 1.5.1-r7 |
| Chainguard | pinot-fips | 1.5.1-r6 |
| Chainguard | ranger | no fix |
| Chainguard | request-9047-keycloak-fips-26.4 | 26.4.7-r26 |
| Chainguard | request-9047-keycloak-fips-26.4-iamguarded-fips | 26.4.7-r26 |
| Chainguard | request-9047-keycloak-fips-26.4-operator | 26.4.7-r26 |
| Chainguard | request-9047-keycloak-fips-26.5 | 26.5.7-r16 |
| Chainguard | request-9047-keycloak-fips-26.5-iamguarded-fips | 26.5.7-r16 |
| Chainguard | request-9047-keycloak-fips-26.5-operator | 26.5.7-r16 |
| Chainguard | request-9047-keycloak-fips-26.6 | 26.6.4-r7 |
| Chainguard | request-9047-keycloak-fips-26.6-iamguarded-fips | 26.6.4-r7 |
| Chainguard | request-9047-keycloak-fips-26.6-operator | 26.6.4-r7 |
| Chainguard | seata-server | 2.7.0-r3 |
| Chainguard | tez | 0.10.5-r24 |
| Chainguard | thingsboard-tb-mqtt-transport | 4.3.1.3-r11 |
| Chainguard | thingsboard-tb-node | 4.3.1.3-r11 |
| Chainguard | zipkin | 3.6.1-r18 |
| Debian 12 | netty | no fix |
| Debian 13 | netty | no fix |
| Debian 14 | netty | no fix |
| SUSE Linux Enterprise High Performance Computing 15 SP4-ESPOS | netty-tcnative | 2.0.80-150200.3.48.1 |
| SUSE Linux Enterprise High Performance Computing 15 SP4-LTSS | netty-tcnative | 2.0.80-150200.3.48.1 |
| SUSE Linux Enterprise High Performance Computing 15 SP5-ESPOS | netty-tcnative | 2.0.80-150200.3.48.1 |
| SUSE Linux Enterprise High Performance Computing 15 SP5-LTSS | netty-tcnative | 2.0.80-150200.3.48.1 |
| SUSE Linux Enterprise Module for Development Tools 15 SP7 | netty-tcnative | 2.0.80-150200.3.48.1 |
| SUSE Linux Enterprise Module for Package Hub 15 SP7 | netty | 4.1.136-150200.4.53.1 |
| SUSE Linux Enterprise Server 15 SP4-LTSS | netty-tcnative | 2.0.80-150200.3.48.1 |
| SUSE Linux Enterprise Server 15 SP5-LTSS | netty-tcnative | 2.0.80-150200.3.48.1 |
| SUSE Linux Enterprise Server 15 SP6-LTSS | netty-tcnative | 2.0.80-150200.3.48.1 |
| SUSE Linux Enterprise Server for SAP Applications 15 SP4 | netty-tcnative | 2.0.80-150200.3.48.1 |
| SUSE Linux Enterprise Server for SAP Applications 15 SP5 | netty-tcnative | 2.0.80-150200.3.48.1 |
| SUSE Linux Enterprise Server for SAP Applications 15 SP6 | netty-tcnative | 2.0.80-150200.3.48.1 |
| Ubuntu 26.10 | netty | no fix |
| Ubuntu Pro 14.04 LTS | netty | no fix |
| Ubuntu Pro 16.04 LTS | netty | no fix |
| Ubuntu Pro 18.04 LTS | netty | no fix |
| Ubuntu Pro 20.04 LTS | netty | no fix |
| Ubuntu Pro 22.04 LTS | netty | no fix |
| Ubuntu Pro 24.04 LTS | netty | no fix |
| Ubuntu Pro 26.04 LTS | netty | no fix |
| Wolfi | apache-activemq-artemis | 2.55.0-r1 |
| Wolfi | apache-pulsar-4.1 | 4.1.3-r15 |
| Wolfi | apache-pulsar-4.2 | 4.2.3-r3 |
| Wolfi | apicurio-registry | 3.3.0-r11 |
| Wolfi | celeborn-0.6 | 0.6.3-r12 |
| Wolfi | keycloak-26.5 | no fix |
| Wolfi | keycloak-26.5-iamguarded-compat | no fix |
| Wolfi | keycloak-26.5-operator | no fix |
| Wolfi | keycloak-26.6 | 26.6.6-r0 |
| Wolfi | keycloak-26.6-iamguarded-compat | 26.6.6-r0 |
| Wolfi | keycloak-26.6-operator | 26.6.6-r0 |
| Wolfi | management-api-for-apache-cassandra-5.0 | 0.1.122-r2 |
| Wolfi | neo4j-2026.05 | 2026.05.0-r12 |
| Wolfi | neo4j-2026.05-docker-publish | no fix |
| Wolfi | neo4j-2026.06 | 2026.06.0-r4 |
| Wolfi | tez | 0.10.5-r24 |
| Wolfi | thingsboard-tb-mqtt-transport | 4.3.1.3-r11 |
| Wolfi | thingsboard-tb-node | 4.3.1.3-r11 |
| Wolfi | zipkin | 3.6.1-r18 |
| openSUSE Tumbleweed | netty | 4.1.136-1.1 |