Netty HTTP/1HTTP/2 Host Header Conflict Allows Unauthorized Access
CVE-2026-93569 Published on September 18, 2026

Io.netty/netty-codec-http2: http/1 absolute-form host mismatch is translated to http/2 :authority, overriding the request-target authority
A flaw was found in Netty. A remote unauthenticated attacker can exploit a vulnerability in Netty's HTTP/1 to HTTP/2 conversion process. When an HTTP/1 request includes both an absolute-form request-target and a conflicting Host header, Netty incorrectly prioritizes the Host header for the HTTP/2 :authority field, discarding the original request-target authority. This inconsistency can allow an attacker to bypass security controls in Netty-based proxies or gateways, potentially leading to unauthorized access, cache poisoning, or misrouting of requests.

Vendor Advisory Vendor Advisory Vendor Advisory NVD

Vulnerability Analysis

CVE-2026-93569 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 a small impact on confidentiality, a high impact on integrity, and no impact on availability.

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

Timeline

Reported to Red Hat.

Made public.

Weakness Type

What is a HTTP Request Smuggling Vulnerability?

When malformed or abnormal HTTP requests are interpreted by one or more entities in the data flow between the user and the web server, such as a proxy or firewall, they can be interpreted inconsistently, allowing the attacker to "smuggle" a request to one device without the other device being aware of it.

CVE-2026-93569 has been classified to as a HTTP Request Smuggling vulnerability or weakness.


Products Associated with CVE-2026-93569

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Red Hat Amq Broker
 
Red Hat Camel Quarkus
 
Red Hat Camel Spring Boot
 
Red Hat Apicurio Registry
 
Red Hat Debezium
 
Red Hat Build Keycloak
 
Red Hat Quarkus
 
Red Hat Jboss Data Grid
 
Red Hat Jboss Fuse
 
Red Hat Jboss Enterprise Application Platform
 
Red Hat Single Sign On
 
Red Hat Apache Camel Quarkus
 

Affected Versions

Red Hat Build of Apache Camel 3.33.3.SP2: Red Hat build of Quarkus 3.27.5.SP2: Red Hat build of Quarkus 3.33.3.SP2: Red Hat AMQ Broker 7: 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 Fuse 7: Red Hat JBoss Enterprise Application Platform 7: Red Hat JBoss Enterprise Application Platform 8: Red Hat Single Sign-On 7: