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

> CVE-2026-33871: Netty HTTP/2 CONTINUATION Frame Flood DoS via Zero-Byte Frame Bypass. CVSS 7.5 (CVSS 3.1).

Canonical: https://rewindex.com/cve/CVE-2026-33871
Last updated: 2026-09-15T12:04:27Z

- Published: 2026-03-27 19:55 UTC · Updated: 2026-09-15 12:04 UTC · Assigner: GitHub\_M
- CVSS: 7.5 (CVSS 3.1) · Severity: High · Vector: CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H
- EPSS: 1.1%, 67th percentile (scored 2026-10-25)
- CISA KEV: no
- CWE: CWE-770

## Description

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.

## Affected vendors and products

- netty: netty
- Red Hat: Cryostat 4
- Red Hat: Logging Subsystem for Red Hat OpenShift
- Red Hat: Red Hat AMQ Broker 7.12.7
- Red Hat: Red Hat AMQ Broker 7.13.5
- Red Hat: Red Hat AMQ Broker 7.14.0
- Red Hat: Red Hat AMQ Clients
- Red Hat: Red Hat Build of Apache Camel 4.14 for Quarkus 3.27
- Red Hat: Red Hat build of Apache Camel 4.18.1 for Spring Boot 3.5.14
- Red Hat: Red Hat build of Apache Camel 4 for Quarkus 3
- Red Hat: Red Hat build of Apache Camel - HawtIO 4
- Red Hat: Red Hat build of Apicurio Registry 3
- Red Hat: Red Hat build of Debezium 2
- Red Hat: Red Hat build of Debezium 3
- Red Hat: Red Hat Build of Keycloak
- Red Hat: Red Hat build of OptaPlanner 8
- Red Hat: Red Hat build of Quarkus
- Red Hat: Red Hat build of Quarkus 3.20.6
- Red Hat: Red Hat Data Grid 8.6.1
- Red Hat: Red Hat Enterprise Linux AI (RHEL AI) 3
- Red Hat: Red Hat Fuse 7
- Red Hat: Red Hat JBoss Enterprise Application Platform 7
- Red Hat: Red Hat JBoss Enterprise Application Platform 8
- Red Hat: Red Hat JBoss Enterprise Application Platform 8.1
- Red Hat: Red Hat JBoss Enterprise Application Platform 8.1 for RHEL 8
- Red Hat: Red Hat JBoss Enterprise Application Platform 8.1 for RHEL 9
- Red Hat: Red Hat JBoss Enterprise Application Platform Expansion Pack
- Red Hat: Red Hat OpenShift AI (RHOAI)
- Red Hat: Red Hat Process Automation 7
- Red Hat: Streams for Apache Kafka 2.9.4
- Red Hat: streams for Apache Kafka 3
- Red Hat: Streams for Apache Kafka 3.2.0

## Tracked companies

- [Bitbucket](https://rewindex.com/company/bitbucket.md)
- [Confluence](https://rewindex.com/company/confluence.md)
- [Jira](https://rewindex.com/company/jira.md)

## References

- [CVE record on cve.org](https://www.cve.org/CVERecord?id=CVE-2026-33871)
- [NVD entry](https://nvd.nist.gov/vuln/detail/CVE-2026-33871)
- [https://github.com/netty/netty/security/advisories/GHSA-w9fj-cfpg-grvv](https://github.com/netty/netty/security/advisories/GHSA-w9fj-cfpg-grvv)

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_Sources: CVE records from the CVE Program (cve.org). CVE® is a registered trademark of The MITRE Corporation. (https://www.cve.org/) This product uses data from the NVD API but is not endorsed or certified by the NVD. (https://nvd.nist.gov/) Known Exploited Vulnerabilities catalog from CISA. (https://www.cisa.gov/known-exploited-vulnerabilities-catalog) EPSS scores from FIRST (Exploit Prediction Scoring System). (https://www.first.org/epss/)_


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Canonical: https://rewindex.com/cve/CVE-2026-33871 · Markdown: https://rewindex.com/cve/CVE-2026-33871.md · JSON: https://rewindex.com/api/v1/cves/CVE-2026-33871 · Data licensed CC BY 4.0 (https://creativecommons.org/licenses/by/4.0/) · Generated 2026-10-26T02:50:29.329Z