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TI-2026-30867 Aliases CVE-2026-42587GHSA-f6hv-jmp6-3vwv

Netty: HttpContentDecompressor maxAllocation bypass via Content-Encoding: br/zstd/snappy enables decompression bomb DoS

Priority HIGH 72CWE-400Published · Updated

Key facts

Attack vector
Network
Privileges required
None
User interaction
None
Attack complexity
Low
Impact type
Denial of service
Confidentiality · integrity · availability
None · None · High
Fix status
Partial Red Hat: 27 fixed, 11 without a fix

Attack profile from CVSS 3.1 · CNA. Fix status from CNA, GitHub and Red Hat. Impact type from CWE-400.

Summary

Netty is an asynchronous, event-driven network application framework. Prior to 4.2.13.Final and 4.1.133.Final, HttpContentDecompressor accepts a maxAllocation parameter to limit decompression buffer size and prevent decompression bomb attacks. This limit is correctly enforced for gzip and deflate encodings via ZlibDecoder, but is silently ignored when the content encoding is br (Brotli), zstd, or snappy. An attacker can bypass the configured decompression limit by sending a compressed payload with Content-Encoding: br instead of Content-Encoding: gzip, causing unbounded memory allocation and out-of-memory denial of service. The same vulnerability exists in DelegatingDecompressorFrameListener for HTTP/2 connections. This vulnerability is fixed in 4.2.13.Final and 4.1.133.Final.

Why it matters now

Exploitation Proof of concept CISA SSVC · not in CISA KEV
EPSS 0.0099 62nd percentileScored 2026-11-07
Public exploit Yes 1 exploit referenceTagged by NVD
Fix Partial netty (netty): 4.2.13.Final, 4.1.133.Finalnetty-codec-http (io.netty): 4.2.13.Final, 4.1.133.Final+3 more productsRed Hat: 28 advisoriesRed Hat: 27 fixed, 11 without a fix

SSVC decision points

CISA ADP · SSVC 2.0.3

Exploitation
Poc
Automatable
Yes
Technical impact
Partial

The decision (Track, Attend, Act) also depends on your mission and well-being impact; see CISA's SSVC guide.

Affected products

VendorProductAffected versionsFixed inStatusSource
nettynetty4.2.0.Alpha1 to before 4.2.13.Final; before 4.1.133.Final4.2.13.Final, 4.1.133.FinalPatch availableCNA
nettynetty-codec-http4.2.0.Alpha1 to before 4.2.13.Final; before 4.1.133.Final4.2.13.Final, 4.1.133.FinalPatch availableCNA
nettynetty-codec-http24.2.0.Alpha1 to before 4.2.13.Final; before 4.1.133.Final4.2.13.Final, 4.1.133.FinalPatch availableCNA
—io.netty:netty-codec-http (Maven)4.2.0.Alpha1 to before 4.2.13.Final4.2.13.FinalPatch availableGHSA-f6hv-jmp6-3vwv
—io.netty:netty-codec-http2 (Maven)4.2.0.Alpha1 to before 4.2.13.Final4.2.13.FinalPatch availableGHSA-f6hv-jmp6-3vwv
—io.netty:netty-codec-http (Maven)before 4.1.133.Final4.1.133.FinalPatch availableGHSA-f6hv-jmp6-3vwv
—io.netty:netty-codec-http2 (Maven)before 4.1.133.Final4.1.133.FinalPatch availableGHSA-f6hv-jmp6-3vwv
  • netty Vendornetty Affected 4.2.0.Alpha1 to before 4.2.13.Final; before 4.1.133.Final Fixed in 4.2.13.Final, 4.1.133.Final Patch available CNA
  • netty-codec-http Vendornetty Affected 4.2.0.Alpha1 to before 4.2.13.Final; before 4.1.133.Final Fixed in 4.2.13.Final, 4.1.133.Final Patch available CNA
  • netty-codec-http2 Vendornetty Affected 4.2.0.Alpha1 to before 4.2.13.Final; before 4.1.133.Final Fixed in 4.2.13.Final, 4.1.133.Final Patch available CNA
  • io.netty:netty-codec-http (Maven) Vendor— Affected 4.2.0.Alpha1 to before 4.2.13.Final Fixed in 4.2.13.Final Patch available GHSA-f6hv-jmp6-3vwv
  • io.netty:netty-codec-http2 (Maven) Vendor— Affected 4.2.0.Alpha1 to before 4.2.13.Final Fixed in 4.2.13.Final Patch available GHSA-f6hv-jmp6-3vwv
  • io.netty:netty-codec-http (Maven) Vendor— Affected before 4.1.133.Final Fixed in 4.1.133.Final Patch available GHSA-f6hv-jmp6-3vwv
  • io.netty:netty-codec-http2 (Maven) Vendor— Affected before 4.1.133.Final Fixed in 4.1.133.Final Patch available GHSA-f6hv-jmp6-3vwv

CPE configurations NVD · 1

CPEVersionsRoleVendor
cpe:2.3:a:netty:netty:*:*:*:*:*:*:*:*before 4.1.133; 4.2.0 to before 4.2.13Vulnerablenetty
  • cpe:2.3:a:netty:netty:*:*:*:*:*:*:*:* Versions before 4.1.133; 4.2.0 to before 4.2.13 Vulnerable ·netty

Remediation

  • Fix · CNA netty (netty) Fixed in 4.2.13.Final, 4.1.133.Final
  • Fix · CNA netty-codec-http (io.netty) Fixed in 4.2.13.Final, 4.1.133.Final
  • Fix · CNA netty-codec-http2 (io.netty) Fixed in 4.2.13.Final, 4.1.133.Final
  • Fix · GHSA-f6hv-jmp6-3vwv io.netty:netty-codec-http (Maven) Fixed in 4.2.13.Final Advisory →
  • Fix · GHSA-f6hv-jmp6-3vwv io.netty:netty-codec-http2 (Maven) Fixed in 4.2.13.Final Advisory →
  • Fix · GHSA-f6hv-jmp6-3vwv io.netty:netty-codec-http (Maven) Fixed in 4.1.133.Final Advisory →
  • Fix · GHSA-f6hv-jmp6-3vwv io.netty:netty-codec-http2 (Maven) Fixed in 4.1.133.Final Advisory →

Red Hat 28 advisories

  • RHSA-2026:84734 Released 2026-10-19 · Red Hat rating Critical
    RHOAI 3.4.5 - Red Hat OpenShift AI
    • Red Hat OpenShift AI 3.4 registry.redhat.io/rhoai/odh-ai-gateway-payload-processing-rhel9, registry.redhat.io/rhoai/odh-automl-rhel9, registry.redhat.io/rhoai/odh-autorag-rhel9 +47
  • RHSA-2026:76128 Released 2026-10-06 · Red Hat rating Important
    Red Hat Single Sign-On 7.6.13 security update on RHEL 7
    • Red Hat Single Sign-On 7.6 for RHEL 7 Server rh-sso7-keycloak-18.0.20-1.redhat_00001.1.el7sso, rh-sso7-keycloak-server-18.0.20-1.redhat_00001.1.el7sso
  • RHSA-2026:76130 Released 2026-10-06 · Red Hat rating Important
    Red Hat Single Sign-On 7.6.13 security update on RHEL 9
    • Red Hat Single Sign-On 7.6 for RHEL 9 rh-sso7-keycloak-18.0.20-1.redhat_00001.1.el9sso, rh-sso7-keycloak-server-18.0.20-1.redhat_00001.1.el9sso
Show 25 more Red Hat advisories
  • RHSA-2026:76129 Released 2026-10-06 · Red Hat rating Important
    Red Hat Single Sign-On 7.6.13 security update on RHEL 8
    • Red Hat Single Sign-On 7.6 for RHEL 8 rh-sso7-keycloak-18.0.20-1.redhat_00001.1.el8sso, rh-sso7-keycloak-server-18.0.20-1.redhat_00001.1.el8sso
  • RHSA-2026:76134 Released 2026-10-05 · Red Hat rating Important
    Red Hat Single Sign-On 7.6.13 for OpenShift image security update
    • Middleware Containers for OpenShift rh-sso-7/sso76-openshift-rhel8
  • RHSA-2026:76132 Released 2026-10-05 · Red Hat rating Important
    Red Hat Single Sign-On 7.6.13 security update
    • Red Hat Single Sign-On 7.6.13
  • RHSA-2026:69459 Released 2026-09-21 · Red Hat rating Important
    AMQ Clients 2026.Q3
    • AMQ Clients 2026.Q3
  • RHSA-2026:66545 Released 2026-09-10 · Red Hat rating Important
    Red Hat AMQ Broker 7.13.6 release and security update
    • Red Hat AMQ Broker 7.13.6
  • RHSA-2026:66488 Released 2026-09-10 · Red Hat rating Important
    Red Hat AMQ Broker 7.14.1 release and security update
    • Red Hat AMQ Broker 7.14.1
  • RHSA-2026:65126 Released 2026-09-08 · Red Hat rating Important
    RHOAI 2.25.11 - Red Hat OpenShift AI
    • Red Hat OpenShift AI 2.25 registry.redhat.io/rhoai/odh-built-in-detector-rhel9, registry.redhat.io/rhoai/odh-caikit-tgis-serving-rhel9, registry.redhat.io/rhoai/odh-dashboard-rhel9 +47
  • RHSA-2026:54435 Released 2026-08-12 · Red Hat rating Important
    Streams for Apache Kafka 3.2.1 release and security update
    • Streams for Apache Kafka 3.2.1
  • RHSA-2026:53806 Released 2026-08-11 · Red Hat rating Important
    Red Hat JBoss Enterprise Application Platform 7.4.25 security update
    • Red Hat JBoss Enterprise Application Platform 7.4.25
  • RHSA-2026:53646 Released 2026-08-11 · Red Hat rating Important
    Red Hat JBoss Enterprise Application Platform 7.4.25 Security update
    • Red Hat JBoss EAP 7.4 ELS for RHEL 9 eap7-activemq-artemis-2.16.0-22.redhat_00057.1.el9eap, eap7-activemq-artemis-cli-2.16.0-22.redhat_00057.1.el9eap, eap7-activemq-artemis-commons-2.16.0-22.redhat_00057.1.el9eap +47
  • RHSA-2026:53645 Released 2026-08-11 · Red Hat rating Important
    Red Hat JBoss Enterprise Application Platform 7.4.25 Security update
    • Red Hat JBoss EAP 7.4 ELS for RHEL 8 eap7-activemq-artemis-2.16.0-22.redhat_00057.1.el8eap, eap7-activemq-artemis-cli-2.16.0-22.redhat_00057.1.el8eap, eap7-activemq-artemis-commons-2.16.0-22.redhat_00057.1.el8eap +47
  • RHSA-2026:53644 Released 2026-08-11 · Red Hat rating Important
    Red Hat JBoss Enterprise Application Platform 7.4.25 security pdate
    • Red Hat JBoss EAP 7.4 ELS for RHEL 7 Server eap7-activemq-artemis-2.16.0-22.redhat_00057.1.el7eap, eap7-activemq-artemis-cli-2.16.0-22.redhat_00057.1.el7eap, eap7-activemq-artemis-commons-2.16.0-22.redhat_00057.1.el7eap +47
  • RHSA-2026:50085 Released 2026-08-04 · Red Hat rating Important
    Red Hat JBoss Enterprise Application Platform 8.1.7.1 XP 6.0.5.1 release
    • Red Hat JBoss Enterprise Application Platform 6.0.5.GA io.netty.netty-codec-http2-4.1.135.Final-redhat-00001.jar
  • RHSA-2026:49700 Released 2026-08-03 · Red Hat rating Important
    Red Hat JBoss Enterprise Application Platform 8.1.7 security update
    • Red Hat JBoss EAP 8.1 for RHEL 10 eap8-eap-product-conf-parent-801.7.1-1.GA_redhat_00001.1.el10eap, eap8-eap-product-conf-wildfly-ee-feature-pack-801.7.1-1.GA_redhat_00001.1.el10eap, eap8-netty-4.1.135-1.Final_redhat_00001.1.el10eap +17
    • Red Hat JBoss EAP 8.1 for RHEL 8 eap8-eap-product-conf-parent-801.7.1-1.GA_redhat_00001.1.el8eap, eap8-eap-product-conf-wildfly-ee-feature-pack-801.7.1-1.GA_redhat_00001.1.el8eap, eap8-jose4j-0.9.6-2.redhat_00002.1.el8eap +19
    • Red Hat JBoss EAP 8.1 for RHEL 9 eap8-eap-product-conf-parent-801.7.1-1.GA_redhat_00001.1.el9eap, eap8-eap-product-conf-wildfly-ee-feature-pack-801.7.1-1.GA_redhat_00001.1.el9eap, eap8-jose4j-0.9.6-2.redhat_00002.1.el9eap +19
  • RHSA-2026:49701 Released 2026-08-03 · Red Hat rating Important
    Red Hat JBoss Enterprise Application Platform 8.1.7 security update
    • Red Hat JBoss Enterprise Application Platform 8.1.7.GA io.netty.netty-codec-dns-4.1.135.Final-redhat-00001.jar, io.netty.netty-codec-http-4.1.135.Final-redhat-00001.jar, io.netty.netty-handler-4.1.135.Final-redhat-00001.jar +2
  • RHSA-2026:42644 Released 2026-07-21 · Red Hat rating Important
    RHOAI 2.25.9 - Red Hat OpenShift AI
    • Red Hat OpenShift AI 2.25 registry.redhat.io/rhoai/odh-caikit-tgis-serving-rhel9, registry.redhat.io/rhoai/odh-feature-server-rhel9, registry.redhat.io/rhoai/odh-kserve-storage-initializer-rhel9 +36
  • RHSA-2026:41951 Released 2026-07-20 · Red Hat rating Important
    Red Hat Data Grid 8.6.2 security update
    • Red Hat Data Grid 8.6.2
  • RHSA-2026:37390 Released 2026-07-09 · Red Hat rating Important
    Red Hat Build of Apache Camel 4.18.1.P1 for Spring Boot release.
    • Red Hat build of Apache Camel 4.18.1.P1 for Spring Boot 3.5.16
  • RHSA-2026:36820 Released 2026-07-08 · Red Hat rating Important
    Red Hat OpenShift Dev Spaces 3.29.0 Release.
    • Red Hat OpenShift Dev Spaces 3.29 registry.redhat.io/devspaces/code-rhel9, registry.redhat.io/devspaces/dashboard-rhel9, registry.redhat.io/devspaces/multicluster-redirector-rhel9 +6
  • RHSA-2026:34608 Released 2026-07-02 · Red Hat rating Important
    Streams for Apache Kafka 2.9.4 release and security update
    • Streams for Apache Kafka 2.9.4
  • RHSA-2026:30049 Released 2026-06-25 · Red Hat rating Important
    Red Hat build of Keycloak 26.4.13 Security Update
    • Red Hat build of Keycloak 26.4.13
  • RHSA-2026:28010 Released 2026-06-22 · Red Hat rating Important
    Red Hat build of Cryostat security update
    • Cryostat 4 on RHEL 9 cryostat/cryostat-openshift-console-plugin-rhel9, cryostat/cryostat-reports-rhel9, cryostat/cryostat-rhel9 +3
  • RHSA-2026:25123 Released 2026-06-10 · Red Hat rating Important
    Red Hat OpenShift Dev Spaces 3.28.2 Release.
    • Red Hat OpenShift Dev Spaces 3.28 registry.redhat.io/devspaces/dashboard-rhel9, registry.redhat.io/devspaces/openvsx-rhel9, registry.redhat.io/devspaces/pluginregistry-rhel9 +1
  • RHSA-2026:24502 Released 2026-06-10 · Red Hat rating Important
    Red Hat build of Quarkus 3.33.2 release and security update
    • Red Hat build of Quarkus 3.33.2.redhat io.netty.netty-codec-dns-4.1.133.Final-redhat-00002.jar, io.netty.netty-codec-http-4.1.133.Final-redhat-00002.jar, io.netty.netty-handler-proxy-4.1.133.Final-redhat-00002.jar
  • RHSA-2026:23808 Released 2026-06-10 · Red Hat rating Important
    Red Hat build of Quarkus 3.27.4 release and security update
    • Red Hat build of Quarkus 3.27.4.redhat io.netty.netty-codec-dns-4.1.133.Final-redhat-00002.jar, io.netty.netty-codec-http-4.1.133.Final-redhat-00002.jar, io.netty.netty-codec-http2-4.1.133.Final-redhat-00002.jar +1

Vendor assessments

Red Hat

Red Hat rating: Important. Red Hat's page for this CVE →

ProductStatusPlan or fix
Cryostat 4AffectedNo fix yet
OpenShift ServerlessAffectedNo fix yet
Red Hat Build of KeycloakAffectedNo fix yet
Red Hat Fuse 7AffectedNo fix planned: Will not fix
Red Hat JBoss Enterprise Application Platform Expansion PackAffectedNo fix yet
Red Hat Process Automation 7AffectedNo fix planned: Will not fix
Red Hat build of Apicurio Registry 2AffectedNo fix planned: Will not fix
Red Hat build of Apicurio Registry 3AffectedNo fix yet
Red Hat build of Debezium 3AffectedNo fix planned: Will not fix
Red Hat build of OptaPlanner 8AffectedNo fix yet
Red Hat build of QuarkusAffectedNo fix yet
AMQ Clients 2026.Q3Fixed RHSA-2026:69459
Cryostat 4 on RHEL 9Fixed RHSA-2026:28010
Middleware Containers for OpenShiftFixed RHSA-2026:76134
Red Hat AMQ Broker 7.13.6Fixed RHSA-2026:66545
Red Hat AMQ Broker 7.14.1Fixed RHSA-2026:66488
Red Hat Data Grid 8.6.2Fixed RHSA-2026:41951
Red Hat JBoss EAP 7.4 ELS for RHEL 7 ServerFixed RHSA-2026:53644
Red Hat JBoss EAP 8.1 for RHEL 10Fixed RHSA-2026:49700
Red Hat JBoss EAP 8.1 for RHEL 8Fixed RHSA-2026:49700
Red Hat JBoss EAP 8.1 for RHEL 9Fixed RHSA-2026:49700
Red Hat JBoss Enterprise Application Platform 6.0.5.GAFixed RHSA-2026:50085
Red Hat JBoss Enterprise Application Platform 7.4.25Fixed RHSA-2026:53806
Red Hat JBoss Enterprise Application Platform 8.1.7.GAFixed RHSA-2026:49701
Red Hat OpenShift AI 2.25Fixed RHSA-2026:42644, RHSA-2026:65126
Red Hat OpenShift AI 3.4Fixed RHSA-2026:84734
Red Hat OpenShift Dev Spaces 3.28Fixed RHSA-2026:25123
Red Hat OpenShift Dev Spaces 3.29Fixed RHSA-2026:36820
Red Hat Single Sign-On 7.6 for RHEL 7 ServerFixed RHSA-2026:76128
Red Hat Single Sign-On 7.6 for RHEL 8Fixed RHSA-2026:76129
Red Hat Single Sign-On 7.6 for RHEL 9Fixed RHSA-2026:76130
Red Hat Single Sign-On 7.6.13Fixed RHSA-2026:76132
Red Hat build of Apache Camel 4.18.1.P1 for Spring Boot 3.5.16Fixed RHSA-2026:37390
Red Hat build of Keycloak 26.4.13Fixed RHSA-2026:30049
Red Hat build of Quarkus 3.27.4.redhatFixed RHSA-2026:23808
Red Hat build of Quarkus 3.33.2.redhatFixed RHSA-2026:24502
Streams for Apache Kafka 2.9.4Fixed RHSA-2026:34608
Streams for Apache Kafka 3.2.1Fixed RHSA-2026:54435
Not affected: 14 products
  • Cryostat 4 on RHEL 9
  • Red Hat Enterprise Linux AI (RHEL AI) 3
  • Red Hat JBoss Enterprise Application Platform 6.0.5.GA
  • Red Hat JBoss Enterprise Application Platform 8.1.7.GA
  • Red Hat OpenShift AI (RHOAI)
  • Red Hat OpenShift AI 2.25
  • Red Hat OpenShift AI 3.4
  • Red Hat OpenShift Dev Spaces 3.28
  • Red Hat OpenShift Dev Spaces 3.29
  • Red Hat Satellite 6
  • Red Hat build of Apache Camel 4 for Quarkus 3
  • Red Hat build of Quarkus 3.27.4.redhat
  • Red Hat build of Quarkus 3.33.2.redhat
  • streams for Apache Kafka 2

Timeline

  1. 2026-10-02 Threatist record created from CVE-2026-42587
  2. 2026-10-03 Alias added: GHSA-f6hv-jmp6-3vwv
  3. 2026-10-06 Fix available: RHSA-2026:76134 · Red Hat
  4. 2026-10-06 Fix available: RHSA-2026:76132 · Red Hat
  5. 2026-10-06 Fix available: RHSA-2026:76129 · Red Hat
  6. 2026-10-06 Fix available: RHSA-2026:76130 · Red Hat
  7. 2026-10-06 Fix available: Middleware Containers for OpenShift, Red Hat Single Sign-On 7.6 for RHEL 8, Red Hat Single Sign-On 7.6 for RHEL 9 +1 · Red Hat
  8. 2026-10-07 Fix available: RHSA-2026:76128 · Red Hat
  9. 2026-10-07 Fix available: Red Hat Single Sign-On 7.6 for RHEL 7 Server · Red Hat
  10. 2026-10-09 Fix available: Red Hat JBoss Enterprise Application Platform 8.1 · Red Hat
  11. 2026-10-20 Fix available: RHSA-2026:84734 · Red Hat
  12. 2026-10-20 Fix available: Red Hat JBoss Enterprise Application Platform 6.0.5.GA, Red Hat OpenShift AI 3.4, Red Hat build of Quarkus 3.27.4.redhat +1 · Red Hat
  13. 2026-10-21 Affected versions changed · Red Hat
  14. 2026-10-23 Fix available: RHSA-2026:30049 · Red Hat
  15. 2026-10-23 Fix available: Red Hat build of Keycloak 26.4.13 · Red Hat
  16. 2026-11-01 Affected versions changed · Red Hat
  17. 2026-11-03 Affected versions changed · Red Hat
  18. 2026-11-06 Fix available: RHSA-2026:42644 · Red Hat

References

Exploit 1

Advisory 1

Other 1

  • TI-2023-23979 The HTTP/2 protocol allows a denial of service (server resource consumption) because… KEVCVSS 3.1HIGH 7.5
  • TI-2026-30861 Netty: HTTP/1.0 TE+CL Coexistence Bypasses Smuggling Sanitization CVSS 3.1CRITICAL 9.8
  • TI-2026-30864 Netty: HttpClientCodec response desynchronization CVSS 3.1CRITICAL 9.1
  • TI-2026-30859 Netty: DNS Codec Input Validation Bypass in Netty (Encoder + Decoder) CVSS 3.1CRITICAL 9.1
  • TI-2026-40973 Netty: Missing CertificateID Validation in OCSP Response Allows Replay Attacks CVSS 3.1CRITICAL 9.1
  • TI-2026-40972 Uncontrolled resource consumption in netty CVSS 3.1HIGH 7.5
See all 92 →

Sources

This product uses the NVD API but is not endorsed or certified by the NVD. Sources and licences