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.
Affected products
netty: netty
References5
- github.com/netty/netty/security/advisories/GHSA-mvh2-crg5-v77c ExploitVendor Advisory
- github.com/netty/netty/commit/5b68c61f37aa4a3045cba624cbea23965… Patch
- github.com/netty/netty/commit/bb2ff68a1fb71cb4b0eb9a9e17b66c52a… Patch
- github.com/netty/netty/releases/tag/netty-4.1.136.Final Release Notes
- 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: 52 · as of 14 November 2026
- CWE
- CWE-400
Could this be exploited in your environment?
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