CVE-2026-55833
Published:July 20, 2026
Updated:August 04, 2026
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 Packages
io.netty:netty-codec-http (JAVA):
Affected version(s) >=4.1.0.Final <4.1.136.FinalFix Suggestion:
Update to version 4.1.136.Finalio.netty:netty-codec-http (JAVA):
Affected version(s) >=4.2.0.Final <4.2.16.FinalFix Suggestion:
Update to version 4.2.16.Finalio.netty:netty-codec-http (JAVA):
Affected version(s) >=4.1.0.Final <4.1.136.FinalFix Suggestion:
Update to version 4.1.136.FinalRelated Resources (8)
Do you need more information?
Contact UsCVSS v4
Base Score:
8.7
Attack Vector
NETWORK
Attack Complexity
LOW
Attack Requirements
NONE
Privileges Required
NONE
User Interaction
NONE
Vulnerable System Confidentiality
NONE
Vulnerable System Integrity
NONE
Vulnerable System Availability
HIGH
Subsequent System Confidentiality
NONE
Subsequent System Integrity
NONE
Subsequent System Availability
NONE
CVSS v3
Base Score:
7.5
Attack Vector
NETWORK
Attack Complexity
LOW
Privileges Required
NONE
User Interaction
NONE
Scope
UNCHANGED
Confidentiality
NONE
Integrity
NONE
Availability
HIGH
Weakness Type (CWE)
Uncontrolled Resource Consumption
EPSS
Base Score:
0.42