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

No CVSS.

References

Link	Resource
https://github.com/netty/netty/commit/5b68c61f37aa4a3045cba624cbea239655c9003b
https://github.com/netty/netty/commit/bb2ff68a1fb71cb4b0eb9a9e17b66c52aff680c6
https://github.com/netty/netty/releases/tag/netty-4.1.136.Final
https://github.com/netty/netty/releases/tag/netty-4.2.16.Final
https://github.com/netty/netty/security/advisories/GHSA-jppx-w49h-x2qq

Configurations

No configuration.

History

21 Jul 2026, 22:17

Type	Values Removed	Values Added
New CVE

Information

Published : 2026-07-21 22:17

Updated : 2026-07-22 20:35

NVD link : CVE-2026-56745

Mitre link : CVE-2026-56745

CVE.ORG link : CVE-2026-56745

JSON object : View

Products Affected

No product.

CWE

CWE-400

Uncontrolled Resource Consumption

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