CVE-2026-55833 (GCVE-0-2026-55833)

Vulnerability from cvelistv5 – Published: 2026-07-20 23:18 – Updated: 2026-07-21 13:03
VLAI
Title
Netty SPDY zlib header block continues decoded expansion after maxHeaderSize truncation
Summary
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.
Severity
7.5 (High)
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H
SSVC
Exploitation: none Automatable: yes Technical Impact: partial
CISA Coordinator · CISA-ADP (v2.0.3)
Decision recorded 2026-07-21 13:03 UTC
CWE
  • CWE-400 - Uncontrolled Resource Consumption
Assigner
References
Impacted products
Vendor Product Version CPE status
netty netty Affected: >= 4.2.0.Final, < 4.2.16.Final
Affected: >= 4.1.0.Final, < 4.1.136.Final
guessed Create a notification for this product.
Show details on NVD website
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