CVE-2026-56816
Published:July 21, 2026
Updated:August 04, 2026
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 Packages
https://github.com/netty/netty.git (GITHUB):
Affected version(s) >=netty-4.2.5.Final <netty-4.2.16.FinalFix Suggestion:
Update to version netty-4.2.16.Finalio.netty:netty-codec-http3 (JAVA):
Affected version(s) >=4.2.2.Final <4.2.16.FinalFix Suggestion:
Update to version 4.2.16.Finalio.netty:netty-codec-http3 (JAVA):
Affected version(s) >=4.2.2.Final <4.2.16.FinalFix Suggestion:
Update to version 4.2.16.FinalRelated Resources (6)
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:
0.52