CVE WatchJul 21, 2026

CVE-2026-55833

Netty is a network application framework for development of protocol servers and clients. Prior to 4.1.136.Final and 4.2.16.Final, Netty SPD

CVSS

7.5

High

EPSS

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KEV

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Exploit Today

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0-100

Published: Jul 21, 2026 · Last modified: Jul 21, 2026 · CWE-400

EPSS · 30d

Not enough EPSS history yet.

Technical description

Netty is a network application framework for development of protocol servers and clients. Prior to 4.1.136.Final and 4.2.16.Final, Netty SPDY header decoding continues inflating zlib-compressed header blocks after the raw header parser has exceeded `maxHeaderSize` and marked the frame truncated in `SpdyFrameCodec`, allowing a remote peer to send a small compressed `HEADERS` block that expands into much larger raw header data and causes compression-amplified CPU and allocation churn. This issue is fixed in versions 4.1.136.Final and 4.2.16.Final.

Official references

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