Netty HTTP/2 DoS via Flooded CONTINUATION frames (V4.1.132/4.2.10 fix)
CVE-2026-33871 Published on March 27, 2026

Netty HTTP/2 CONTINUATION Frame Flood DoS via Zero-Byte Frame Bypass
Netty is an asynchronous, event-driven network application framework. In versions prior to 4.1.132.Final and 4.2.10.Final, a remote user can trigger a Denial of Service (DoS) against a Netty HTTP/2 server by sending a flood of `CONTINUATION` frames. The server's lack of a limit on the number of `CONTINUATION` frames, combined with a bypass of existing size-based mitigations using zero-byte frames, allows an user to cause excessive CPU consumption with minimal bandwidth, rendering the server unresponsive. Versions 4.1.132.Final and 4.2.10.Final fix the issue.

NVD

Vulnerability Analysis

CVE-2026-33871 can be exploited with network access, and does not require authorization privileges or user interaction. This vulnerability is considered to have a low attack complexity. The potential impact of an exploit of this vulnerability is considered to have no impact on confidentiality and integrity, and a high impact on availability.

Attack Vector:
NETWORK
Attack Complexity:
LOW
Privileges Required:
NONE
User Interaction:
NONE
Scope:
UNCHANGED
Confidentiality Impact:
NONE
Integrity Impact:
NONE
Availability Impact:
HIGH

Weakness Type

Allocation of Resources Without Limits or Throttling

The software allocates a reusable resource or group of resources on behalf of an actor without imposing any restrictions on the size or number of resources that can be allocated, in violation of the intended security policy for that actor.


Products Associated with CVE-2026-33871

You can be notified by email with stack.watch whenever vulnerabilities like CVE-2026-33871 are published in these products:

Netty
 
Red Hat Kafka
 
Red Hat Jboss Enterprise Application Platform
 
Red Hat Cryostat
 
Red Hat Amq Broker
 
Red Hat Apache Camel Quarkus
 
Red Hat Jboss Data Grid
 
Red Hat Openshift Ai
 
Red Hat Openshift Devspaces
 
Red Hat Apache Camel Spring Boot
 
Red Hat Quarkus
 
Red Hat Amq Streams
 
Red Hat Logging
 
Red Hat Serverless
 
Red Hat Amq Clients
 
Red Hat Apache Camel Hawtio
 
Red Hat Camel Quarkus
 
Red Hat Service Registry
 
Red Hat Apicurio Registry
 
Red Hat Debezium
 
Red Hat Build Keycloak
 
Red Hat Optaplanner
 
Red Hat Enterprise Linux Ai
 
Red Hat Jboss Fuse
 
Red Hat Jbosseapxp
 
Red Hat Jboss Enterprise Bpms Platform
 
Red Hat Single Sign On
 
Red Hat Satellite
 

Affected Versions

netty: Red Hat Cryostat 4 on RHEL 9: Red Hat Cryostat 4 on RHEL 9: Red Hat Cryostat 4 on RHEL 9: Red Hat AMQ Broker 7.12.7: Red Hat AMQ Broker 7.13.5: Red Hat AMQ Broker 7.14.0: Red Hat Build of Apache Camel 4.14 for Quarkus 3.27: Red Hat build of Apache Camel 4.18.1 for Spring Boot 3.5.14: Red Hat build of Quarkus 3.20.6: Red Hat build of Quarkus 3.27.3: Red Hat Data Grid 8.6.1: Red Hat JBoss Enterprise Application Platform 8.1: Red Hat JBoss Enterprise Application Platform 8.1: Red Hat JBoss Enterprise Application Platform 8.1 for RHEL 8: Red Hat JBoss Enterprise Application Platform 8.1 for RHEL 8: Red Hat JBoss Enterprise Application Platform 8.1 for RHEL 9: Red Hat JBoss Enterprise Application Platform 8.1 for RHEL 9: Red Hat Streams for Apache Kafka 2.9.4: Red Hat Streams for Apache Kafka 3.2.0: Red Hat OpenShift AI 2.25: Red Hat OpenShift Dev Spaces 3.27: Red Hat OpenShift Dev Spaces 3.27: Red Hat OpenShift Dev Spaces 3.27: Red Hat Cryostat 4: Logging Subsystem for Red Hat OpenShift: Logging Subsystem for Red Hat OpenShift: Logging Subsystem for Red Hat OpenShift: Logging Subsystem for Red Hat OpenShift: Logging Subsystem for Red Hat OpenShift: Logging Subsystem for Red Hat OpenShift: Red Hat OpenShift Serverless: Red Hat OpenShift Serverless: Red Hat OpenShift Serverless: Red Hat OpenShift Serverless: Red Hat OpenShift Serverless: Red Hat OpenShift Serverless: Red Hat OpenShift Serverless: Red Hat OpenShift Serverless: Red Hat OpenShift Serverless: Red Hat OpenShift Serverless: Red Hat AMQ Clients: Red Hat build of Apache Camel 4 for Quarkus 3: Red Hat build of Apache Camel 4 for Quarkus 3: Red Hat build of Apache Camel - HawtIO 4: Red Hat build of Apache Camel - HawtIO 4: Red Hat build of Apicurio Registry 2: Red Hat build of Apicurio Registry 2: Red Hat build of Apicurio Registry 3: Red Hat build of Apicurio Registry 3: Red Hat build of Debezium 2: Red Hat build of Debezium 2: Red Hat build of Debezium 3: Red Hat build of Debezium 3: Red Hat Build of Keycloak: Red Hat Build of Keycloak: Red Hat build of OptaPlanner 8: Red Hat build of OptaPlanner 8: Red Hat build of Quarkus: Red Hat Enterprise Linux AI (RHEL AI) 3: Red Hat Enterprise Linux AI (RHEL AI) 3: Red Hat Enterprise Linux AI (RHEL AI) 3: Red Hat Fuse 7: Red Hat Fuse 7: Red Hat JBoss Enterprise Application Platform 7: Red Hat JBoss Enterprise Application Platform 7: Red Hat JBoss Enterprise Application Platform 8: Red Hat JBoss Enterprise Application Platform 8: Red Hat JBoss Enterprise Application Platform Expansion Pack: Red Hat JBoss Enterprise Application Platform Expansion Pack: Red Hat JBoss Enterprise Application Platform Expansion Pack: Red Hat JBoss Enterprise Application Platform Expansion Pack: Red Hat JBoss Enterprise Application Platform Expansion Pack: Red Hat JBoss Enterprise Application Platform Expansion Pack: Red Hat OpenShift AI (RHOAI): Red Hat OpenShift AI (RHOAI): Red Hat OpenShift AI (RHOAI): Red Hat Process Automation 7: Red Hat Process Automation 7: Red Hat Satellite 6: Red Hat Satellite 6: Red Hat Single Sign-On 7: Red Hat Single Sign-On 7: Red Hat streams for Apache Kafka 3: Red Hat streams for Apache Kafka 3:

Exploit Probability

EPSS
0.60%
Percentile
44.22%

EPSS (Exploit Prediction Scoring System) scores estimate the probability that a vulnerability will be exploited in the wild within the next 30 days. The percentile shows you how this score compares to all other vulnerabilities.