CVE-2026-56816

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.

CVSS v3 7.5 HIGH

7.5^/10

CVSS v3 : HIGH

Vector :

Exploitability : 3.9 / Impact : 3.6

Attack Vector NETWORK

Attack Complexity LOW

Privileges Required NONE

User Interaction NONE

Confidentiality Impact NONE

Integrity Impact NONE

Availability Impact HIGH

Scope UNCHANGED

References

Link	Resource
https://github.com/netty/netty/commit/5b68c61f37aa4a3045cba624cbea239655c9003b	Patch
https://github.com/netty/netty/releases/tag/netty-4.2.16.Final	Release Notes
https://github.com/netty/netty/security/advisories/GHSA-hpcc-26xq-25fv	Exploit Vendor Advisory

Configurations

Configuration 1 (hide)

cpe:2.3:a:netty:netty:*:*:*:*:*:*:*:*

History

No history.

Information

Published : 2026-07-21 22:17

Updated : 2026-08-07 20:47

NVD link : CVE-2026-56816

Mitre link : CVE-2026-56816

CVE.ORG link : CVE-2026-56816

JSON object : View

Products Affected

netty

netty

CWE

CWE-400

Uncontrolled Resource Consumption

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