{"id":"CVE-2026-33871","title":"Netty is an asynchronous, event-driven network application framework","summary":"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 `CONTINUAT…","severity":"high","cvss":7.5,"cvssVector":"CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H","cwe":["CWE-770"],"vendor":"netty","product":"netty","affected":["netty < 4.1.132","netty >= 4.2.0, < 4.2.10"],"patched":["netty 4.2.10"],"published":"2026-03-27","updated":"2026-09-14","sourceUpdated":"2026-09-14T13:18:18.077","source":"NVD","sourceUrl":"https://nvd.nist.gov/vuln/detail/CVE-2026-33871","references":[{"url":"https://github.com/netty/netty/security/advisories/GHSA-w9fj-cfpg-grvv","label":"security-advisories@github.com"},{"url":"https://access.redhat.com/errata/RHSA-2026:10175","label":"0b0ca135-0b70-47e7-9f44-1890c2a1c46c"},{"url":"https://access.redhat.com/errata/RHSA-2026:10184","label":"0b0ca135-0b70-47e7-9f44-1890c2a1c46c"},{"url":"https://access.redhat.com/errata/RHSA-2026:13571","label":"0b0ca135-0b70-47e7-9f44-1890c2a1c46c"},{"url":"https://access.redhat.com/errata/RHSA-2026:14272","label":"0b0ca135-0b70-47e7-9f44-1890c2a1c46c"},{"url":"https://access.redhat.com/errata/RHSA-2026:14276","label":"0b0ca135-0b70-47e7-9f44-1890c2a1c46c"},{"url":"https://access.redhat.com/errata/RHSA-2026:17668","label":"0b0ca135-0b70-47e7-9f44-1890c2a1c46c"},{"url":"https://access.redhat.com/errata/RHSA-2026:17789","label":"0b0ca135-0b70-47e7-9f44-1890c2a1c46c"},{"url":"https://access.redhat.com/errata/RHSA-2026:18054","label":"0b0ca135-0b70-47e7-9f44-1890c2a1c46c"},{"url":"https://access.redhat.com/errata/RHSA-2026:18055","label":"0b0ca135-0b70-47e7-9f44-1890c2a1c46c"},{"url":"https://access.redhat.com/errata/RHSA-2026:18059","label":"0b0ca135-0b70-47e7-9f44-1890c2a1c46c"},{"url":"https://access.redhat.com/errata/RHSA-2026:22619","label":"0b0ca135-0b70-47e7-9f44-1890c2a1c46c"},{"url":"https://access.redhat.com/errata/RHSA-2026:34608","label":"0b0ca135-0b70-47e7-9f44-1890c2a1c46c"},{"url":"https://access.redhat.com/errata/RHSA-2026:65126","label":"0b0ca135-0b70-47e7-9f44-1890c2a1c46c"},{"url":"https://access.redhat.com/errata/RHSA-2026:7109","label":"0b0ca135-0b70-47e7-9f44-1890c2a1c46c"},{"url":"https://access.redhat.com/errata/RHSA-2026:7380","label":"0b0ca135-0b70-47e7-9f44-1890c2a1c46c"},{"url":"https://access.redhat.com/errata/RHSA-2026:8159","label":"0b0ca135-0b70-47e7-9f44-1890c2a1c46c"},{"url":"https://access.redhat.com/errata/RHSA-2026:8509","label":"0b0ca135-0b70-47e7-9f44-1890c2a1c46c"},{"url":"https://access.redhat.com/security/cve/CVE-2026-33871","label":"0b0ca135-0b70-47e7-9f44-1890c2a1c46c"},{"url":"https://bugzilla.redhat.com/show_bug.cgi?id=2452456","label":"0b0ca135-0b70-47e7-9f44-1890c2a1c46c"},{"url":"https://security.access.redhat.com/data/csaf/v2/vex/2026/cve-2026-33871.json","label":"0b0ca135-0b70-47e7-9f44-1890c2a1c46c"},{"url":"https://www.cve.org/CVERecord?id=CVE-2026-33871"},{"url":"https://nvd.nist.gov/vuln/detail/CVE-2026-33871"}],"tags":["nvd","cve.org","csaf","vex","red-hat"],"ssvc":{"exploitation":"none","automatable":"yes","technicalImpact":"partial","timestamp":"2026-03-31T18:51:31.168118Z"},"scores":{"nvd":7.5,"cna":8.7,"vendor":7.5},"epss":0.01125,"epssPercentile":0.64355,"ingestedAt":"2026-07-03T14:03:36.914Z","slug":"CVE-2026-33871","body":"## Overview\n\nNetty 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.\n\n## Affected\n\n- `netty < 4.1.132`\n- `netty >= 4.2.0, < 4.2.10`\n\n## Remediation\n\nUpgrade past the affected range:\n\n- `netty 4.2.10`\n\n## Vendor advisories\n\n- **RHSA-2026:18054** · Red Hat · fixed in: Red Hat JBoss EAP 8.1 for RHEL 8 · released 2026-05-18 · [advisory](https://access.redhat.com/errata/RHSA-2026:18054)\n- **RHSA-2026:17789** · Red Hat · fixed in: Cryostat 4 on RHEL 9 · released 2026-05-26 · [advisory](https://access.redhat.com/errata/RHSA-2026:17789)\n- **RHSA-2026:18055** · Red Hat · fixed in: Red Hat JBoss EAP 8.1 for RHEL 9 · released 2026-05-18 · [advisory](https://access.redhat.com/errata/RHSA-2026:18055)\n- **RHSA-2026:14276** · Red Hat · fixed in: Red Hat AMQ Broker 7.12.7 · released 2026-05-06 · [advisory](https://access.redhat.com/errata/RHSA-2026:14276)\n- **RHSA-2026:14272** · Red Hat · fixed in: Red Hat AMQ Broker 7.13.5 · released 2026-05-06 · [advisory](https://access.redhat.com/errata/RHSA-2026:14272)\n- **RHSA-2026:8509** · Red Hat · fixed in: Red Hat AMQ Broker 7.14.0 · released 2026-04-16 · [advisory](https://access.redhat.com/errata/RHSA-2026:8509)\n- **RHSA-2026:8159** · Red Hat · fixed in: Red Hat Build of Apache Camel 4.14 for Quarkus 3.27 · released 2026-04-14 · [advisory](https://access.redhat.com/errata/RHSA-2026:8159)\n- **RHSA-2026:22619** · Red Hat · fixed in: Red Hat Data Grid 8.6.1 · released 2026-06-02 · [advisory](https://access.redhat.com/errata/RHSA-2026:22619)\n- **RHSA-2026:18059** · Red Hat · fixed in: Red Hat JBoss Enterprise Application Platform 8.1 · released 2026-05-18 · [advisory](https://access.redhat.com/errata/RHSA-2026:18059)\n- **RHSA-2026:10184** · Red Hat · fixed in: Red Hat OpenShift AI 2.25 · released 2026-04-23 · [advisory](https://access.redhat.com/errata/RHSA-2026:10184)\n- **RHSA-2026:65126** · Red Hat · fixed in: Red Hat OpenShift AI 2.25 · released 2026-09-08 · [advisory](https://access.redhat.com/errata/RHSA-2026:65126)\n- **Red Hat VEX** · Important · affected: Cryostat 4, Logging Subsystem for Red Hat OpenShift, OpenShift Serverless, Red Hat AMQ Clients, Red Hat build of Apache Camel - HawtIO 4, Red Hat build of Apache Camel 4 for Quarkus 3, … · no fix planned: OpenShift Serverless, Red Hat build of Apicurio Registry 2, Red Hat build of Debezium 3, Red Hat build of OptaPlanner 8, … · updated 2026-09-14 · [vex](https://security.access.redhat.com/data/csaf/v2/vex/2026/cve-2026-33871.json)","depth":"twilight","depthScore":41,"depthScoreParts":{"impact":41.3,"likelihood":0.2,"exploitation":0,"ransomware":0},"changes":[]}