Medium 5.8Published May 13, 2026

CVE-2026-42581Netty: HTTP/1.0 TE+CL Coexistence Bypasses Smuggling Sanitization

Updated under an hour ago (Oct 28, 2026, 6:10 AM ET)

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It affects netty and 24 other products. Add what you run to find out whether that includes you.

No exploitation reported and no EPSS estimate yet.

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Every CVE for netty

Exploited in the last 30 days

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.

CVSS: 5.8 MEDIUM (v3.1, CNA)CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:C/C:N/I:L/A:N
Weakness (CWE): CWE-444
Known exploited: Not in CISA's KEV catalog
EPSS (exploitation in the next 30 days): Not loaded for this CVE
Assigned by: GitHub_M
NVD analysis: Modified
Record last updated: Sep 18, 2026
First seen by InfoSec Signals: Oct 9, 2026

Affected products

Affected products

netty netty netty:netty (from the name)	from 4.2.0.Alpha1, < 4.2.13.Final; before 4.1.133.Final	CNA record
Red Hat Cryostat 4 on RHEL 9 redhat:cryostat	from 4.2.0-10 not affected	CISA ADP
Red Hat Red Hat AMQ Broker 7.13.6 redhat:amq_broker	from codec-http not affected	CISA ADP
Red Hat Red Hat build of Apache Camel 4.18.1.P1 for Spring Boot 3.5.16 redhat:apache_camel_spring_boot	from codec-http not affected	CISA ADP
Red Hat Red Hat build of Quarkus 3.27.4 redhat:quarkus	from codec-http not affected	CISA ADP
Red Hat Red Hat JBoss Enterprise Application Platform 7.4 ELS on RHEL 7 redhat:jboss_enterprise_application_platform_els	from 0:2.16.0-22.redhat_00057.1.el7eap not affected	CISA ADP
Red Hat Red Hat JBoss Enterprise Application Platform 8.1.7.GA redhat:jboss_enterprise_application_platform	from 4.1.135.Final-redhat-00001 not affected	CISA ADP
Red Hat Streams for Apache Kafka 3.2.1 redhat:amq_streams	from codec-http not affected	CISA ADP
Red Hat Red Hat OpenShift AI 2.25 redhat:openshift_ai	from 1783443816 not affected	CISA ADP
Red Hat Red Hat OpenShift Dev Spaces 3.28 redhat:openshift_devspaces	from 1780948325 not affected	CISA ADP
1–10 of 26

References

References

https://github.com/netty/netty/security/advisories/GHSA-xxqh-mfjm-7mv9	x-refsource-confirm, exploit, mitigation, vendor-advisory
https://access.redhat.com/errata/RHSA-2026:23808
https://access.redhat.com/errata/RHSA-2026:24502
https://access.redhat.com/errata/RHSA-2026:25123
https://access.redhat.com/errata/RHSA-2026:28010
https://access.redhat.com/errata/RHSA-2026:36820
https://access.redhat.com/errata/RHSA-2026:37390
https://access.redhat.com/errata/RHSA-2026:42644
https://access.redhat.com/errata/RHSA-2026:49700
https://access.redhat.com/errata/RHSA-2026:49701
1–10 of 20

The CVE record on cve.org NVD's entry

The CVE record is authoritative. Products marked “from the name” were identified from the CNA's free-text names, not a CPE, and are matched less certainly. This product uses the NVD API but is not endorsed or certified by the NVD.