High 8.7Published Mar 27, 2026

CVE-2026-33871Netty HTTP/2 CONTINUATION Frame Flood DoS via Zero-Byte Frame Bypass

Updated under an hour ago (Oct 26, 2026, 3:40 PM ET)

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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. In versions prior to 4.1.132.Final and 4.2.10.Final, a remote user can trigger a Denial of Service (DoS) against a Netty HTTP/2 server by sending a flood of `CONTINUATION` frames. The server's lack of a limit on the number of `CONTINUATION` frames, combined with a bypass of existing size-based mitigations using zero-byte frames, allows an user to cause excessive CPU consumption with minimal bandwidth, rendering the server unresponsive. Versions 4.1.132.Final and 4.2.10.Final fix the issue.

CVSS: 8.7 HIGH (v4.0, CNA)CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:N/VI:N/VA:H/SC:N/SI:N/SA:N
Weakness (CWE): CWE-770
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 15, 2026
First seen by InfoSec Signals: Oct 9, 2026

Affected products

Affected products

netty netty netty:netty (from the name)	before 4.1.132.Final; from 4.2.0.Alpha1, < 4.2.10.Final	CNA record
Red Hat Cryostat 4 on RHEL 9 redhat:cryostat	from 4.2.0-9 not affected	CISA ADP
Red Hat Red Hat AMQ Broker 7.12.7 redhat:amq_broker	from codec-http2 not affected	CISA ADP
Red Hat Red Hat Build of Apache Camel 4.14 for Quarkus 3.27 redhat:apache_camel_quarkus	from codec-http2 not affected	CISA ADP
Red Hat Red Hat build of Apache Camel 4.18.1 for Spring Boot 3.5.14 redhat:apache_camel_spring_boot	from codec-http not affected; from codec-http2 not affected	CISA ADP
Red Hat Red Hat build of Quarkus 3.20.6 redhat:quarkus	from codec-http2 not affected	CISA ADP
Red Hat Red Hat Data Grid 8.6.1 redhat:jboss_data_grid	from codec-http not affected; from codec-http2 not affected	CISA ADP
Red Hat Red Hat JBoss Enterprise Application Platform 8.1 redhat:jboss_enterprise_application_platform	from codec-http not affected	CISA ADP
Red Hat Streams for Apache Kafka 2.9.4 redhat:amq_streams	from codec-http not affected; from codec-http2 not affected	CISA ADP
Red Hat Red Hat OpenShift AI 2.25 redhat:openshift_ai	from 1776756834 not affected	CISA ADP
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References

References

https://github.com/netty/netty/security/advisories/GHSA-w9fj-cfpg-grvv	x-refsource-confirm, vendor-advisory
https://access.redhat.com/errata/RHSA-2026:10175
https://access.redhat.com/errata/RHSA-2026:10184
https://access.redhat.com/errata/RHSA-2026:13571
https://access.redhat.com/errata/RHSA-2026:14272
https://access.redhat.com/errata/RHSA-2026:14276
https://access.redhat.com/errata/RHSA-2026:17668
https://access.redhat.com/errata/RHSA-2026:17789
https://access.redhat.com/errata/RHSA-2026:18054
https://access.redhat.com/errata/RHSA-2026:18055
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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.