CVE-2026-93574: Io.netty/netty-codec-http: netty: http request smuggling via post-digit whitespace in chunk-size parsing

Severity: medium (CVSS 6.5 v3.1)
Exploited in the wild: not listed in CISA KEV
EPSS: 1.4% 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-444

Description

A flaw was found in Netty's `netty-codec-http` component. A remote attacker could exploit this vulnerability by sending a specially crafted HTTP/1.1 chunk-size token that includes post-digit whitespace. This incorrect parsing of the chunk size can lead to HTTP request smuggling. This allows an attacker to bypass security controls or access unauthorized resources in proxy/backend deployments.

Affected products

Red Hat build of Keycloak 26.4: all versions
Red Hat AMQ Broker 7: all versions
Red Hat AMQ Clients: all versions
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 Data Grid 8: all versions
Red Hat JBoss Enterprise Application Platform 8: all versions

References

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