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Fencer Vulns
high 7.5

CVE-2026-56745 json

Netty SpdyHttpDecoder: ByteBuf Reference Leak on RST_STREAM Leads to Native Memory Exhaustion

published 2026-07-21 3 mo ago modified 2026-09-10 1 mo ago also EUVD-2026-46452 , GHSA-jppx-w49h-x2qq

cvss
7.5
version 3.1, NVD
cisa kev
Not listed
not in CISA's catalog
epss
0.6%
EPSS 0.6% chance of exploitation in 30 days, percentile 50%
public exploits
0
none known

Summary

Netty is a network application framework for development of protocol servers and clients. In versions 4.2.0.Final through 4.2.15.Final and 4.1.0.Final through 4.1.135.Final, the `SpdyHttpDecoder` handler in Netty's SPDY-to-HTTP codec allocates a pooled `ByteBuf` when processing a client-initiated `SYN_STREAM` frame with `FLAG_FIN=0` and stores the partially constructed `FullHttpRequest` in `messageMap`; when the remote peer sends `RST_STREAM` for that stream or the accumulated content exceeds `maxContentLength`, the decoder removes the entry but does not release the pooled `ByteBuf`, causing native memory exhaustion. This issue is fixed in versions 4.1.136.Final and 4.2.16.Final.

Patch / fix

  • maven io.netty:netty-codec-http 4.1.136.Final, 4.2.16.Final
  • io.netty netty-codec-http 4.1.136.Final, 4.2.16.Final
  • netty netty 4.1.136.Final, 4.2.16.Final
  • eap8-jaxb jboss enterprise application platform 8.1 4.0.7-4.redhat_00001.1.el10eap
  • eap8-txw2 jboss enterprise application platform 8.1 4.0.7-4.redhat_00001.1.el10eap
  • eap8-xsom jboss enterprise application platform 8.1 4.0.7-4.redhat_00001.1.el10eap
  • eap8-log4j jboss enterprise application platform 8.1 2.25.4-1.redhat_00003.1.el10eap
  • eap8-netty jboss enterprise application platform 8.1 4.1.136-1.Final_redhat_00001.1.el10eap
  • eap8-rngom jboss enterprise application platform 8.1 4.0.7-4.redhat_00001.1.el10eap
  • eap8-slf4j jboss enterprise application platform 8.1 2.0.18-1.redhat_00001.1.el10eap
  • eap8-neethi jboss enterprise application platform 8.1 3.2.2-1.redhat_00001.1.el10eap

red hat advisories RHSA-2026:70230RHSA-2026:70229RHSA-2026:70228

  • netty-tcnative SLES for SAP 15 SP6, SLES for SAP 15 SP5, SLES for SAP 15 SP4 +8 more 2.0.80-150200.3.48.1
  • netty SLE Module for Package Hub 15 SP7 4.1.136-150200.4.53.1

suse advisories SUSE-SU-2026:3482-1

  • netty openSUSE Tumbleweed 4.1.136-1.1

opensuse advisories openSUSE-SU-2026:11394-1

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-2026-56745 updated cvss 7.5

netty: io.netty/netty-codec-http: Netty: Denial of Service via memory exhaustion in SPDY-to-HTTP codec

  • Red Hat OpenShift Serverless openshift-serverless-1/kn-ekb-receiver-rhel9, openshift-serverless-1/kn-ekb-dispatcher-rhel9, openshift-serverless-1/kn-eventing-integrations-log-sink-rhel9, openshift-serverless-1/kn-eventing-integrations-aws-s3-sink-rhel9, openshift-serverless-1/kn-eventing-integrations-aws-sns-sink-rhel9, openshift-serverless-1/kn-eventing-integrations-aws-sqs-sink-rhel9, +4 more Red Hat AMQ Clients netty-codec-http 4.1.130.Final-redhat-00001 Red Hat build of Apache Camel - HawtIO 4 netty-codec-http 4.1.130.Final-redhat-00001 Red Hat build of Apache Camel 4 for Quarkus 3 netty-codec-http 4.1.130.Final-redhat-00001
    affected: no fix available
  • Red Hat build of Debezium 3 netty-codec-http 4.1.130.Final-redhat-00001
    affected: no fix planned “Will not fix”
  • Red Hat Build of Keycloak rhbk-keycloak-rhel9, rhbk-rhel9-operator, rhbk-openshift-rhel9, rhbk-keycloak-rhel9-operator, netty-codec-http 4.1.130.Final-redhat-00001 Red Hat Data Grid 8 datagrid-datagrid-8-rhel9, netty-codec-http 4.1.130.Final-redhat-00001 Red Hat Enterprise Linux AI (RHEL AI) 3 bazel6 6.5.0-2.el9ai, bazel7 7.7.1-1.el9ai, bazel8 8.6.0-1.el9ai
    affected: no fix available
  • Red Hat JBoss Enterprise Application Platform 7 eap74-els-openjdk8-openshift-rhel8, eap74-els-openjdk11-openshift-rhel8, eap74-els-openjdk17-openshift-rhel8, jboss-eap-7-eap74-els-openjdk11-openshift-rhel8, jboss-eap-7-eap74-els-openjdk17-openshift-rhel8
    affected: no fix planned “Will not fix”
  • Red Hat JBoss Enterprise Application Platform 8 netty-codec-http 4.1.130.Final-redhat-00001
    affected: no fix available
  • Red Hat Single Sign-On 7 netty-codec-http 4.1.130.Final-redhat-00001
    affected: no fix planned “Will not fix”
  • Red Hat Cryostat 4 on RHEL 9 cryostat/cryostat-rhel9 4.2.0-14, cryostat/jfr-datasource-rhel9 4.2.0-14, cryostat/cryostat-reports-rhel9 4.2.0-14
    fixed: vendor fix RHSA-2026:68333
  • Red Hat AMQ Broker 7.13.6
    fixed: vendor fix RHSA-2026:66545
show 21 more
  • Red Hat AMQ Broker 7.14.1
    fixed: vendor fix RHSA-2026:66488
  • Red Hat Build of Apache Camel 3.33.2.SP3 netty-codec-http 4.1.136.Final-redhat-00001
    fixed: vendor fix RHSA-2026:48118
  • Red Hat build of Apache Camel 4.18.3 for Spring Boot 3.5.16
    fixed: vendor fix RHSA-2026:54622
  • Red Hat build of Apicurio Registry 3.3.3
    fixed: vendor fix RHSA-2026:76637
  • Red Hat build of Keycloak 26.4.14
    fixed: vendor fix RHSA-2026:50846
  • Red Hat build of Keycloak 26.6.5
    fixed: vendor fix RHSA-2026:50848
  • Red Hat build of Quarkus 3.27.4.SP3 netty-codec-http 4.1.136.Final-redhat-00001
    fixed: vendor fix RHSA-2026:47189
  • Red Hat build of Quarkus 3.33.2.SP3 netty-codec-http 4.1.136.Final-redhat-00001
    fixed: vendor fix RHSA-2026:47172
  • Red Hat Data Grid 8.6.3
    fixed: vendor fix RHSA-2026:69296
  • Red Hat JBoss EAP 8.1 for RHEL 8 eap8-jaxb 4.0.7-4.redhat_00001.1.el8eap, eap8-txw2 4.0.7-4.redhat_00001.1.el8eap, eap8-xsom 4.0.7-4.redhat_00001.1.el8eap, eap8-rngom 4.0.7-4.redhat_00001.1.el8eap, eap8-log4j 2.25.4-1.redhat_00003.1.el8eap, eap8-neethi 3.2.2-1.redhat_00001.1.el8eap, +101 more
    fixed: vendor fix RHSA-2026:70228
  • Red Hat JBoss EAP 8.1 for RHEL 9 eap8-jaxb 4.0.7-4.redhat_00001.1.el9eap, eap8-txw2 4.0.7-4.redhat_00001.1.el9eap, eap8-xsom 4.0.7-4.redhat_00001.1.el9eap, eap8-rngom 4.0.7-4.redhat_00001.1.el9eap, eap8-log4j 2.25.4-1.redhat_00003.1.el9eap, eap8-neethi 3.2.2-1.redhat_00001.1.el9eap, +101 more
    fixed: vendor fix RHSA-2026:70229
  • Red Hat JBoss EAP 8.1 for RHEL 10 eap8-jaxb 4.0.7-4.redhat_00001.1.el10eap, eap8-txw2 4.0.7-4.redhat_00001.1.el10eap, eap8-xsom 4.0.7-4.redhat_00001.1.el10eap, eap8-rngom 4.0.7-4.redhat_00001.1.el10eap, eap8-log4j 2.25.4-1.redhat_00003.1.el10eap, eap8-neethi 3.2.2-1.redhat_00001.1.el10eap, +100 more
    fixed: vendor fix RHSA-2026:70230
  • Red Hat JBoss Enterprise Application Platform 8.1.8.GA netty-codec 4.1.136.Final-redhat-00001, netty-codec-http 4.1.136.Final-redhat-00001
    fixed: vendor fix RHSA-2026:70277
  • Red Hat OpenShift AI 2.25 rhoai/odh-modelmesh-rhel9 1788319539, rhoai/odh-trustyai-service-rhel9 1788198681
    fixed: vendor fix RHSA-2026:65126
  • Red Hat OpenShift AI 3.4 rhoai/odh-trustyai-service-rhel9 1791792525
    fixed: vendor fix RHSA-2026:84734
  • Red Hat OpenShift Dev Spaces 3.30 devspaces/server-rhel9 1789163798, devspaces/openvsx-rhel9 1787759145, devspaces/pluginregistry-rhel9 1787759723
    fixed: vendor fix RHSA-2026:62260
  • Red Hat OpenShift Dev Spaces 3.31 devspaces/jetbrains-ide-rhel9 1792476427, devspaces/multicluster-redirector-rhel9 1792491532
    fixed: vendor fix RHSA-2026:90321
  • Red Hat Streams for Apache Kafka 3.2.1
    fixed: vendor fix RHSA-2026:54435
  • Red Hat Cryostat 4 on RHEL 9 cryostat/cryostat-db-rhel9 4.2.0-22, cryostat/cryostat-storage-rhel9 4.2.0-22, cryostat/cryostat-rhel9-operator 4.2.0-21, cryostat/cryostat-operator-bundle 4.2.0-12, cryostat/cryostat-agent-init-rhel9 0.7.0-12, cryostat/cryostat-grafana-dashboard-rhel9 4.2.0-14, +1 more Red Hat Build of Apache Camel 3.33.2.SP3 jimfs 1.1, jna 5.8.0, bcel 6.7.0, bson 5.6.4, gax 2.74.1, icu4j 78.2, +1630 more Red Hat build of Quarkus 3.27.4.SP3 jna 5.8.0, db2 1.21.4, h2 2.3.230, y18n 5.0.8, cliui 8.0.1, guice 5.1.0, +1009 more Red Hat build of Quarkus 3.33.2.SP3 jna 5.8.0, bson 5.6.4, h2 2.4.240, y18n 5.0.8, cliui 8.0.1, guice 5.1.0, +1018 more Red Hat JBoss Enterprise Application Platform 7 netty-codec-http 4.1.130.Final-redhat-00001 Red Hat JBoss Enterprise Application Platform 8.1.8.GA pom.xml, aesh 2.4, c3 0.6.4, d3 7.4.3, he 1.2.0, lr 1.4.2, +1868 more
    not affected: vulnerable code not present
  • Red Hat JBoss Enterprise Application Platform Expansion Pack netty-codec-http 4.1.130.Final-redhat-00001
    not affected: component not present
  • Red Hat OpenShift AI (RHOAI) rhoai/odh-spark-operator-rhel9, rhoai/odh-th06-cpu-torch210-py312-rhel9, rhoai/odh-th06-cpu-torch291-py312-rhel9, rhoai/odh-th06-rocm64-torch291-py312-rhel9, rhoai/odh-th06-cuda130-torch210-py312-rhel9, rhoai/odh-th06-cuda130-torch291-py312-rhel9 Red Hat OpenShift AI 2.25 rhoai/odh-rhel9-operator 1788331391, rhoai/odh-vllm-cpu-rhel9 1786712073, rhoai/odh-dashboard-rhel9 1788312226, rhoai/odh-operator-bundle 1788332816, rhoai/odh-vllm-cuda-rhel9 1786710989, rhoai/odh-vllm-rocm-rhel9 1786711151, +69 more
    not affected: vulnerable code not present

5 more not affected in the full advisory

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
yes
Technical impact
partial
Assessed
3 mo ago

Exploit prediction

0.63% chance of exploitation in the next 30 days, higher than 50% of all scored CVEs (FIRST EPSS, 2026-11-08).

CVSS scores

assigned by version score vector
CNA 4.0 8.7 CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:N/VI:N/VA:H/SC:N/SI:N/SA:N
CNA 4.0 8.7 CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:N/VI:N/VA:H/SC:N/SI:N/SA:N/E:X/CR:X/IR:X/AR:X/MAV:X/MAC:X/MAT:X/MPR:X/MUI:X/MVC:X/MVI:X/MVA:X/MSC:X/MSI:X/MSA:X/S:X/AU:X/R:X/V:X/RE:X/U:X
NVD 3.1 7.5 CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H

Affected packages

ecosystem package affected fixed in
maven io.netty:netty-codec-http
>=4.2.0.Final, <4.2.16.Final
>=4.1.0.Final, <4.1.136.Final
4.2.16.Final
4.1.136.Final

Affected products

  • netty netty

Classification

Weakness
  • CWE-400 Uncontrolled Resource Consumption

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.