--- id: CVE-2026-55831 title: >- io.netty/netty-codec-http: Netty: Denial of Service via SPDY SETTINGS frame processing (CVE-2026-55831) summary: >- A flaw was found in Netty, a network application framework. A remote attacker, by sending a specially crafted SPDY/3.1 SETTINGS frame, could cause the SPDY SETTINGS decoder to create a large number of map entries. This excessive processing… severity: high cvss: 7.5 cvssVector: 'CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H' cvssSource: vendor cwe: - CWE-770 - CWE-400 vendor: Red Hat product: Red Hat JBoss EAP 8.1 for RHEL 8 affected: - openshift_serverless - amq_clients - build_of_apache_camel_hawtio 4 - build_of_apache_camel_4_for_quarkus 3 - build_of_apicurio_registry 3 - build_of_debezium 3 - build_of_keycloak - enterprise_linux_ai_rhel_ai 3 - jboss_enterprise_application_platform 7 - openshift_ai_rhoai - openshift_dev_spaces - single_sign_on 7 - streams_for_apache_kafka 2 - jboss_eap_8_1_for_rhel 10 - jboss_eap_8_1_for_rhel 8 - cryostat_4_on_rhel 9 - jboss_eap_8_1_for_rhel 9 - amq_broker 7.13.6 - amq_broker 7.14.1 - build_of_apache_camel_4_18_for_quarkus 3.33 - data_grid 8.6.3 - openshift_ai 2.25 - openshift_dev_spaces 3.30 - build_of_apache_camel_4_18_3_for_spring_boot 3.5.16 - build_of_quarkus 3.27.4.SP3 - build_of_quarkus 3.33.2.SP3 - streams_for_apache_kafka 3.2.1 patched: - jboss_eap_8_1_for_rhel 10 - jboss_eap_8_1_for_rhel 8 - cryostat_4_on_rhel 9 - jboss_eap_8_1_for_rhel 9 - amq_broker 7.13.6 - amq_broker 7.14.1 - build_of_apache_camel_4_18_for_quarkus 3.33 - data_grid 8.6.3 - openshift_ai 2.25 - openshift_dev_spaces 3.30 - build_of_apache_camel_4_18_3_for_spring_boot 3.5.16 - build_of_quarkus 3.27.4.SP3 - build_of_quarkus 3.33.2.SP3 - streams_for_apache_kafka 3.2.1 published: '2026-07-20' updated: '2026-09-22' sourceUpdated: '2026-09-22T15:32:24+00:00' source: CSAF sourceUrl: 'https://security.access.redhat.com/data/csaf/v2/vex/2026/cve-2026-55831.json' references: - url: >- https://security.access.redhat.com/data/csaf/v2/vex/2026/cve-2026-55831.json - url: 'https://access.redhat.com/security/cve/CVE-2026-55831' - url: 'https://bugzilla.redhat.com/show_bug.cgi?id=2503103' - url: 'https://www.cve.org/CVERecord?id=CVE-2026-55831' - url: 'https://nvd.nist.gov/vuln/detail/CVE-2026-55831' - url: >- https://github.com/netty/netty/commit/5b68c61f37aa4a3045cba624cbea239655c9003b - url: >- https://github.com/netty/netty/commit/bb2ff68a1fb71cb4b0eb9a9e17b66c52aff680c6 - url: 'https://github.com/netty/netty/releases/tag/netty-4.1.136.Final' - url: 'https://github.com/netty/netty/releases/tag/netty-4.2.16.Final' - url: 'https://github.com/netty/netty/security/advisories/GHSA-6jqx-86gh-f27w' - url: 'https://access.redhat.com/errata/RHSA-2026:70230' - url: 'https://access.redhat.com/errata/RHSA-2026:70228' - url: 'https://access.redhat.com/errata/RHSA-2026:68333' - url: 'https://access.redhat.com/errata/RHSA-2026:70229' - url: 'https://access.redhat.com/errata/RHSA-2026:66545' - url: 'https://access.redhat.com/errata/RHSA-2026:66488' - url: 'https://access.redhat.com/errata/RHSA-2026:48118' - url: 'https://access.redhat.com/errata/RHSA-2026:69296' - url: 'https://access.redhat.com/errata/RHSA-2026:65126' - url: 'https://access.redhat.com/errata/RHSA-2026:62260' - url: 'https://access.redhat.com/errata/RHSA-2026:68754' - url: 'https://access.redhat.com/errata/RHSA-2026:54622' - url: 'https://access.redhat.com/errata/RHSA-2026:47189' - url: 'https://access.redhat.com/errata/RHSA-2026:47172' - url: 'https://access.redhat.com/errata/RHSA-2026:54435' - url: 'https://github.com/advisories/GHSA-6jqx-86gh-f27w' tags: - csaf - vex - red-hat - ghsa - maven epss: 0.00665 epssPercentile: 0.49606 aliases: - GHSA-6jqx-86gh-f27w ecosystem: maven ingestedAt: '2026-07-22T22:06:58.047Z' --- ## Overview A flaw was found in Netty, a network application framework. A remote attacker, by sending a specially crafted SPDY/3.1 SETTINGS frame, could cause the SPDY SETTINGS decoder to create a large number of map entries. This excessive processing and memory allocation can lead to a denial of service (DoS) due to heap growth and increased CPU usage. ## Vendor advisories - **RHSA-2026:70230** · Red Hat · fixed in: Red Hat JBoss EAP 8.1 for RHEL 10 · released 2026-09-22 · [advisory](https://access.redhat.com/errata/RHSA-2026:70230) - **RHSA-2026:70228** · Red Hat · fixed in: Red Hat JBoss EAP 8.1 for RHEL 8 · released 2026-09-22 · [advisory](https://access.redhat.com/errata/RHSA-2026:70228) - **RHSA-2026:68333** · Red Hat · fixed in: Cryostat 4 on RHEL 9 · released 2026-09-16 · [advisory](https://access.redhat.com/errata/RHSA-2026:68333) - **RHSA-2026:70229** · Red Hat · fixed in: Red Hat JBoss EAP 8.1 for RHEL 9 · released 2026-09-22 · [advisory](https://access.redhat.com/errata/RHSA-2026:70229) - **RHSA-2026:66545** · Red Hat · fixed in: Red Hat AMQ Broker 7.13.6 · released 2026-09-10 · [advisory](https://access.redhat.com/errata/RHSA-2026:66545) - **RHSA-2026:66488** · Red Hat · fixed in: Red Hat AMQ Broker 7.14.1 · released 2026-09-10 · [advisory](https://access.redhat.com/errata/RHSA-2026:66488) - **RHSA-2026:48118** · Red Hat · fixed in: Red Hat Build of Apache Camel 4.18 for Quarkus 3.33 · released 2026-07-30 · [advisory](https://access.redhat.com/errata/RHSA-2026:48118) - **RHSA-2026:69296** · Red Hat · fixed in: Red Hat Data Grid 8.6.3 · released 2026-09-21 · [advisory](https://access.redhat.com/errata/RHSA-2026:69296) - **RHSA-2026:65126** · Red Hat · fixed in: Red Hat OpenShift AI 2.25 · released 2026-09-08 · [advisory](https://access.redhat.com/errata/RHSA-2026:65126) - **RHSA-2026:62260** · Red Hat · fixed in: Red Hat OpenShift Dev Spaces 3.30 · released 2026-09-01 · [advisory](https://access.redhat.com/errata/RHSA-2026:62260) - **RHSA-2026:68754** · Red Hat · fixed in: Red Hat OpenShift Dev Spaces 3.30 · released 2026-09-17 · [advisory](https://access.redhat.com/errata/RHSA-2026:68754) - **Red Hat VEX** · Important · affected: OpenShift Serverless, Red Hat AMQ Clients, Red Hat build of Apache Camel - HawtIO 4, Red Hat build of Apache Camel 4 for Quarkus 3, Red Hat build of Apicurio Registry 3, Red Hat build of Debezium 3, … · no fix planned: Red Hat build of Debezium 3, Red Hat JBoss Enterprise Application Platform 7, Red Hat Single Sign-On 7, OpenShift Serverless, … · updated 2026-09-22 · [vex](https://security.access.redhat.com/data/csaf/v2/vex/2026/cve-2026-55831.json) - **RHSA-2026:54622** · Red Hat · fixed in: Red Hat build of Apache Camel 4.18.3 for Spring Boot 3.5.16 · released 2026-08-13 · [advisory](https://access.redhat.com/errata/RHSA-2026:54622) - **RHSA-2026:47189** · Red Hat · fixed in: Red Hat build of Quarkus 3.27.4.SP3 · released 2026-07-29 · [advisory](https://access.redhat.com/errata/RHSA-2026:47189) - **RHSA-2026:47172** · Red Hat · fixed in: Red Hat build of Quarkus 3.33.2.SP3 · released 2026-07-30 · [advisory](https://access.redhat.com/errata/RHSA-2026:47172) - **RHSA-2026:54435** · Red Hat · fixed in: Streams for Apache Kafka 3.2.1 · released 2026-08-12 · [advisory](https://access.redhat.com/errata/RHSA-2026:54435) **io.netty/netty-codec-http: Netty: Denial of Service via SPDY SETTINGS frame processing** — rated Important by Red Hat. Released 2026-07-20, updated 2026-09-22. Affected: - OpenShift Serverless - Red Hat AMQ Clients - Red Hat build of Apache Camel - HawtIO 4 - Red Hat build of Apache Camel 4 for Quarkus 3 - Red Hat build of Apicurio Registry 3 - Red Hat build of Debezium 3 - Red Hat Build of Keycloak - Red Hat Enterprise Linux AI (RHEL AI) 3 - Red Hat JBoss Enterprise Application Platform 7 - Red Hat OpenShift AI (RHOAI) - Red Hat OpenShift Dev Spaces - Red Hat Single Sign-On 7 - streams for Apache Kafka 2 Fixed: - Red Hat JBoss EAP 8.1 for RHEL 10 - Red Hat JBoss EAP 8.1 for RHEL 8 - Cryostat 4 on RHEL 9 - Red Hat JBoss EAP 8.1 for RHEL 9 - Red Hat AMQ Broker 7.13.6 - Red Hat AMQ Broker 7.14.1 - Red Hat Build of Apache Camel 4.18 for Quarkus 3.33 - Red Hat Data Grid 8.6.3 - Red Hat OpenShift AI 2.25 - Red Hat OpenShift Dev Spaces 3.30 - Red Hat build of Apache Camel 4.18.3 for Spring Boot 3.5.16 - Red Hat build of Quarkus 3.27.4.SP3 - Red Hat build of Quarkus 3.33.2.SP3 - Streams for Apache Kafka 3.2.1 No fix planned: - Red Hat build of Debezium 3 - Red Hat JBoss Enterprise Application Platform 7 - Red Hat Single Sign-On 7 - OpenShift Serverless - Red Hat AMQ Clients - Red Hat build of Apache Camel - HawtIO 4 - Red Hat build of Apache Camel 4 for Quarkus 3 - Red Hat build of Apicurio Registry 3 - Red Hat Build of Keycloak - Red Hat Enterprise Linux AI (RHEL AI) 3 - Red Hat OpenShift AI (RHOAI) - Red Hat OpenShift Dev Spaces - streams for Apache Kafka 2 Not affected: - Cryostat 4 on RHEL 9 - Red Hat OpenShift AI 2.25 - Red Hat OpenShift Dev Spaces 3.30 - Red Hat JBoss Enterprise Application Platform Expansion Pack - Red Hat OpenShift AI (RHOAI) - Red Hat Satellite 6 ## Remediation Before applying the update, make sure all previously released errata relevant to your system have been applied. Also, back up your existing installation, including all applications, configuration files, databases and database settings. For details on how to apply this update, refer to: https://access.redhat.com/articles/11258 https://access.redhat.com/errata/RHSA-2026:70230 Before applying the update, make sure all previously released errata relevant to your system have been applied. Also, back up your existing installation, including all applications, configuration files, databases and database settings. For details on how to apply this update, refer to: https://access.redhat.com/articles/11258 https://access.redhat.com/errata/RHSA-2026:70228 Before applying this update, make sure all previously released errata relevant to your system have been applied. For details on how to apply this update, refer to: https://access.redhat.com/articles/11258 https://access.redhat.com/errata/RHSA-2026:68333 Workarounds / mitigations: - Mitigation for this issue is either not available or the currently available options do not meet the Red Hat Product Security criteria comprising ease of use and deployment, applicability to widespread installation base, or stability. ## Package advisory (CVE-2026-55831) Affected packages: - `io.netty:netty-codec-http >= 4.2.0.Final, <= 4.2.15.Final` - `io.netty:netty-codec-http >= 4.1.0.Final, <= 4.1.135.Final` Patched in: - `io.netty:netty-codec-http 4.2.16.Final` - `io.netty:netty-codec-http 4.1.136.Final` Source: https://github.com/advisories/GHSA-6jqx-86gh-f27w