CVE details
CVE-2026-33871
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 ports (1)
| Port | Package | Version | Status | Maintainer |
|---|---|---|---|---|
| java/netty | netty | 4.1.53_2 | unaddressed | glewis@FreeBSD.org |
Template for a VuXML entry
Range taken from the CVE record, check it before committing. make newentry in security/vuxml creates the vid.
<vuln vid="FIXME (make newentry)">
<topic>FIXME -- FIXME</topic>
<affects>
<package>
<name>netty</name>
<range><lt>4.1.132</lt></range>
</package>
</affects>
<description>
<body xmlns="http://www.w3.org/1999/xhtml">
<p>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.</p>
</body>
</description>
<references>
<cvename>CVE-2026-33871</cvename>
<url>https://nvd.nist.gov/vuln/detail/CVE-2026-33871</url>
</references>
<dates>
<discovery>2026-03-27</discovery>
<entry>2026-10-25</entry>
</dates>
</vuln>