Description
Netty is a network application framework for development of protocol servers and clients. Prior to 4.2.16.Final, Netty's `Http3FrameCodec` buffers incoming data for HTTP/3 reserved frame types up to the wire-specified payload length without limits; `decodeFrame` trusts `payLoadLength`, allowing an attacker to open multiple QUIC streams and send reserved frames with very large payload lengths to cause memory exhaustion and denial of service. This issue is fixed in version 4.2.16.Final.
Affected products
netty: netty
References3
- github.com/netty/netty/security/advisories/GHSA-hpcc-26xq-25fv ExploitVendor Advisory
- github.com/netty/netty/commit/5b68c61f37aa4a3045cba624cbea23965… Patch
- github.com/netty/netty/releases/tag/netty-4.2.16.Final Release Notes
Metrics
- CVSS 3.1
-
7.5
HIGH
Score source: CNA
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H - EPSS — exploit probability
- 1% percentile: 51 · as of 14 November 2026
- CWE
- CWE-400
Could this be exploited in your environment?
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