netty-resolver-dns: Netty DNS resolver: DNS Cache Poisoning via predictable transaction IDs (CVE-2026-45673)

Overview

A flaw was found in Netty's DNS resolver component. This vulnerability arises from the use of a predictable pseudo-random number generator (PRNG) for DNS transaction IDs and a static User Datagram Protocol (UDP) source port. This combination significantly reduces the randomness of DNS queries, making it easier for a remote attacker to perform DNS Cache Poisoning, also known as a Kaminsky attack. Successful exploitation could allow an attacker to redirect network traffic to malicious servers.

Vendor advisories

• RHSA-2026:26018 · Red Hat · fixed in: Red Hat build of Quarkus 3.27.4.SP1 · released 2026-06-17 · advisory
• RHSA-2026:26017 · Red Hat · fixed in: Red Hat build of Quarkus 3.33.2.SP1 · released 2026-06-17 · advisory
• Red Hat VEX · Moderate · affected: Cryostat 4, OpenShift Serverless, Red Hat build of Apache Camel - HawtIO 4, Red Hat build of Apache Camel 4 for Quarkus 3, Red Hat build of Apache Camel for Spring Boot 4, Red Hat build of Apicurio Registry 3, … · no fix planned: Cryostat 4, OpenShift Serverless, Red Hat build of Apache Camel - HawtIO 4, Red Hat build of Apache Camel 4 for Quarkus 3, … · updated 2026-10-20 · vex
• RHSA-2026:50085 · Red Hat · fixed in: Red Hat JBoss Enterprise Application Platform 8.1 · released 2026-08-04 · advisory

netty-resolver-dns: Netty DNS resolver: DNS Cache Poisoning via predictable transaction IDs — rated Moderate by Red Hat. Released 2026-06-12, updated 2026-10-20.

Affected:

• Cryostat 4
• OpenShift Serverless
• Red Hat build of Apache Camel - HawtIO 4
• Red Hat build of Apache Camel 4 for Quarkus 3
• Red Hat build of Apache Camel for Spring Boot 4
• Red Hat build of Apicurio Registry 3
• Red Hat build of Debezium 3
• Red Hat Build of Keycloak
• Red Hat Data Grid 8
• Red Hat Enterprise Linux AI (RHEL AI) 3
• Red Hat Fuse 7
• Red Hat JBoss Enterprise Application Platform 7
• Red Hat JBoss Enterprise Application Platform 8
• Red Hat JBoss Enterprise Application Platform Expansion Pack
• Red Hat OpenShift AI (RHOAI)
• Red Hat OpenShift Dev Spaces
• Red Hat Single Sign-On 7
• streams for Apache Kafka 2
• streams for Apache Kafka 3

Fixed:

• Red Hat build of Quarkus 3.27.4.SP1
• Red Hat build of Quarkus 3.33.2.SP1

No fix planned:

• Cryostat 4
• OpenShift Serverless
• Red Hat build of Apache Camel - HawtIO 4
• Red Hat build of Apache Camel 4 for Quarkus 3
• Red Hat build of Apache Camel for Spring Boot 4
• Red Hat build of Apicurio Registry 3
• Red Hat build of Debezium 3
• Red Hat Build of Keycloak
• Red Hat Data Grid 8
• Red Hat Enterprise Linux AI (RHEL AI) 3
• Red Hat Fuse 7
• Red Hat JBoss Enterprise Application Platform 7
• Red Hat JBoss Enterprise Application Platform 8
• Red Hat JBoss Enterprise Application Platform Expansion Pack
• Red Hat OpenShift AI (RHOAI)
• Red Hat OpenShift Dev Spaces
• Red Hat Single Sign-On 7
• streams for Apache Kafka 2
• streams for Apache Kafka 3

Not affected:

• Red Hat build of Quarkus 3.27.4.SP1
• Red Hat build of Quarkus 3.33.2.SP1

Remediation

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-2026:26018 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-2026:26017

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-2026-45673)

Affected packages:

• io.netty:netty-resolver-dns >= 4.2.0.Final, <= 4.2.14.Final
• io.netty:netty-resolver-dns <= 4.1.134.Final

Patched in:

• io.netty:netty-resolver-dns 4.2.15.Final
• io.netty:netty-resolver-dns 4.1.135.Final

Source: https://github.com/advisories/GHSA-xmv7-r254-6q78