CVE-2026-93564: Io.netty/netty-codec-haproxy: netty: haproxy proxy-v2 nested-tlv grandchild bytebuf reference-count leak (incomplete fix of pr #16881)

Severity: high (CVSS 7.5 v3.1)
Exploited in the wild: not listed in CISA KEV
EPSS: 0.9% probability of exploitation in the next 30 days
Public exploit or detection template: none known
Published: 2026-09-18 · updated 2026-10-15
Weakness: CWE-1035

Description

A flaw was found in Netty. A reference-count leak in the HAProxy PROXY-v2 message decoder allows a remote, unauthenticated attacker to send specially crafted PROXY-protocol v2 headers. This can lead to memory exhaustion, resulting in a Denial of Service (DoS) for the affected system.

Affected products

Red Hat build of Keycloak 26.4: all versions
Red Hat AMQ Broker 7: all versions
Red Hat Build of Apache Camel 3.33.3.SP2: all versions — fixed in 4.1.138.Final-redhat-00001
Red Hat build of Apache Camel 4 for Quarkus 3: all versions
Red Hat build of Apache Camel for Spring Boot 4: all versions
Red Hat build of Apicurio Registry 3: all versions
Red Hat Fuse 7: all versions
Red Hat JBoss Enterprise Application Platform 7: all versions
Red Hat Single Sign-On 7: all versions

How to fix

Upgrade to a fixed version: Red Hat Build of Apache Camel 3.33.3.SP2 4.1.138.Final-redhat-00001. Check the vendor advisory for mitigations.

References

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