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TI-2026-30859 Aliases CVE-2026-42579GHSA-cm33-6792-r9fm

Netty: DNS Codec Input Validation Bypass in Netty (Encoder + Decoder)

Priority HIGH 78CWE-20Published · Updated

Key facts

Attack vector
Network
Privileges required
None
User interaction
None
Attack complexity
Low
Impact type
Denial of service
Confidentiality · integrity · availability
None · High · High
Fix status
Partial Red Hat: 21 fixed, 10 without a fix

Attack profile from CVSS 3.1 · NVD. 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, Netty's DNS codec does not enforce RFC 1035 domain name constraints during either encoding or decoding. This creates a bidirectional attack surface: malicious DNS responses can exploit the decoder, and user-influenced hostnames can exploit the encoder. 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 0.01006 63rd percentileScored 2026-11-07
Public exploit Yes 1 exploit referenceTagged by NVD
Fix Partial netty (netty): 4.2.13.Final, 4.1.133.Finalio.netty:netty-codec-dns (Maven): 4.2.13.Final, 4.1.133.FinalRed Hat: 21 advisoriesRed Hat: 21 fixed, 10 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
—io.netty:netty-codec-dns (Maven)4.2.0.Alpha1 to before 4.2.13.Final4.2.13.FinalPatch availableGHSA-cm33-6792-r9fm
—io.netty:netty-codec-dns (Maven)before 4.1.133.Final4.1.133.FinalPatch availableGHSA-cm33-6792-r9fm
  • 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
  • io.netty:netty-codec-dns (Maven) Vendor— Affected 4.2.0.Alpha1 to before 4.2.13.Final Fixed in 4.2.13.Final Patch available GHSA-cm33-6792-r9fm
  • io.netty:netty-codec-dns (Maven) Vendor— Affected before 4.1.133.Final Fixed in 4.1.133.Final Patch available GHSA-cm33-6792-r9fm

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 · GHSA-cm33-6792-r9fm io.netty:netty-codec-dns (Maven) Fixed in 4.2.13.Final Advisory →
  • Fix · GHSA-cm33-6792-r9fm io.netty:netty-codec-dns (Maven) Fixed in 4.1.133.Final Advisory →

Red Hat 21 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 18 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-2026:65126 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-2026:49700 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-2026:37390 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-2026:30049 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
OpenShift ServerlessAffectedNo fix yet
Red Hat Build of KeycloakAffectedNo fix yet
Red Hat Data Grid 8AffectedNo fix planned: Will not fix
Red Hat Enterprise Linux AI (RHEL AI) 3AffectedNo fix planned: Will not fix
Red Hat Fuse 7AffectedNo fix planned: Will not fix
Red Hat JBoss Enterprise Application Platform Expansion PackAffectedNo fix planned: Will not fix
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 Debezium 3AffectedNo fix planned: Will not fix
Red Hat build of OptaPlanner 8AffectedNo fix yet
Cryostat 4 on RHEL 9Fixed RHSA-2026:28010
Middleware Containers for OpenShiftFixed RHSA-2026:76134
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 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-2026:65126
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 3.2.1Fixed RHSA-2026:54435
Not affected: 13 products
  • Cryostat 4 on RHEL 9
  • Red Hat Build of Keycloak
  • 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 build of Apache Camel 4 for Quarkus 3
  • Red Hat build of Apicurio Registry 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-2026-42579
  2. 2026-10-03 Alias added: GHSA-cm33-6792-r9fm
  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. 2026-10-20 Fix available: RHSA-2026:84734 · Red Hat
  11. 2026-10-20 Fix available: Red Hat OpenShift AI 3.4, Red Hat build of Quarkus 3.27.4.redhat, Red Hat build of Quarkus 3.33.2.redhat · Red Hat
  12. 2026-10-21 Affected versions changed · Red Hat
  13. 2026-10-23 Fix available: RHSA-2026:30049 · Red Hat
  14. 2026-10-23 Fix available: Red Hat build of Keycloak 26.4.13 · Red Hat
  15. 2026-11-01 Affected versions changed · Red Hat

References

Exploit 1

Advisory 1

Other 3

  • 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-2026-40973 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
  • TI-2026-40298 Netty SPDY SETTINGS frame count materializes unbounded settings map 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