CVE-2026-42581: Netty: HTTP/1.0 TE+CL Coexistence Bypasses Smuggling Sanitization
Description
Netty is an asynchronous, event-driven network application framework. Prior to 4.2.13.Final and 4.1.133.Final, HttpObjectDecoder strips a conflicting Content-Length header when a request carries both Transfer-Encoding: chunked and Content-Length, but only for HTTP/1.1 messages. The guard is absent for HTTP/1.0. An attacker that sends an HTTP/1.0 request with both headers causes Netty to decode the body as chunked while leaving Content-Length intact in the forwarded HttpMessage. Any downstream proxy or handler that trusts Content-Length over Transfer-Encoding will disagree on message boundaries, enabling request smuggling. This vulnerability is fixed in 4.2.13.Final and 4.1.133.Final.
Vector CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:C/C:N/I:L/A:N · CWE-444
Tracked companies
Mapped from the CVE’s affected-product data, NVD CPE matches, vendor advisories or package feeds. A mapping means the vendor’s software is named, not that its hosted service was exposed.
Status incidents that name it
No tracked status incident names this CVE.
Affected vendors and products
netty: nettyRed Hat: Red Hat AMQ Broker 7.13.6Red Hat: Red Hat AMQ Broker 7.14.1Red Hat: Red Hat AMQ ClientsRed Hat: Red Hat build of Apache Camel 4.18.1.P1 for Spring Boot 3.5.16Red Hat: Red Hat build of Apache Camel 4 for Quarkus 3Red Hat: Red Hat build of Apicurio Registry 3Red Hat: Red Hat build of Debezium 3Red Hat: Red Hat Build of KeycloakRed Hat: Red Hat Data Grid 8Red Hat: Red Hat Enterprise Linux AI (RHEL AI) 3Red Hat: Red Hat JBoss Enterprise Application Platform 7.4 ELS on RHEL 7Red Hat: Red Hat JBoss Enterprise Application Platform 7.4 ELS on RHEL 8Red Hat: Red Hat JBoss Enterprise Application Platform 8.1.7.GARed Hat: Red Hat JBoss Enterprise Application Platform 8.1 for RHEL 10Red Hat: Red Hat JBoss Enterprise Application Platform 8.1 for RHEL 8Red Hat: Red Hat JBoss Enterprise Application Platform 8.1 for RHEL 9Red Hat: streams for Apache Kafka 2Red Hat: Streams for Apache Kafka 3.2.1
References
- CVE record on cve.org (opens in new tab)
- NVD entry (opens in new tab)
- github.com/netty/netty/security/advisories/GHSA-xxqh-mfjm-7mv9 (opens in new tab)
- CVE records from the CVE Program (cve.org). CVE® is a registered trademark of The MITRE Corporation. (opens in new tab)
- This product uses data from the NVD API but is not endorsed or certified by the NVD. (opens in new tab)
- Known Exploited Vulnerabilities catalog from CISA. (opens in new tab)
- EPSS scores from FIRST (Exploit Prediction Scoring System). (opens in new tab)