CVE-2026-56745

Netty is a network application framework for development of protocol servers and clients. In versions 4.2.0.Final through 4.2.15.Final and 4.1.0.Final through 4.1.135.Final, the `SpdyHttpDecoder` handler in Netty's SPDY-to-HTTP codec allocates a pooled `ByteBuf` when processing a client-initiated `SYN_STREAM` frame with `FLAG_FIN=0` and stores the partially constructed `FullHttpRequest` in `messageMap`; when the remote peer sends `RST_STREAM` for that stream or the accumulated content exceeds `maxContentLength`, the decoder removes the entry but does not release the pooled `ByteBuf`, causing native memory exhaustion. This issue is fixed in versions 4.1.136.Final and 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/commit/bb2ff68a1fb71cb4b0eb9a9e17b66c52aff680c6	Patch
https://github.com/netty/netty/releases/tag/netty-4.1.136.Final	Release Notes
https://github.com/netty/netty/releases/tag/netty-4.2.16.Final	Release Notes
https://github.com/netty/netty/security/advisories/GHSA-jppx-w49h-x2qq	Vendor Advisory

Configurations

Configuration 1 (hide)

OR	cpe:2.3:a:netty:netty::::::::
	cpe:2.3:a:netty:netty::::::::

History

No history.

Information

Published : 2026-07-21 22:17

Updated : 2026-07-30 14:46

NVD link : CVE-2026-56745

Mitre link : CVE-2026-56745

CVE.ORG link : CVE-2026-56745

JSON object : View

Products Affected

netty

netty

CWE

CWE-400

Uncontrolled Resource Consumption

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