CVE-2026-56817

Description

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, any caller that can deliver bytes to a Netty channel pipeline containing `XmlDecoder` can send XML with a `DOCTYPE` declaration to an `AsyncXMLInputFactory` instantiated with no security configuration, leaving DTD and entity handling active depending on Aalto XML async parser behavior and creating conditional XML external entity risk. This issue is fixed in versions 4.1.136.Final and 4.2.16.Final.

References

https://github.com/netty/netty/security/advisories/GHSA-4qhr-g3c6-fcfx

https://github.com/netty/netty/releases/tag/netty-4.2.16.Final

https://github.com/netty/netty/releases/tag/netty-4.1.136.Final

https://github.com/netty/netty/commit/bb2ff68a1fb71cb4b0eb9a9e17b66c52aff680c6

https://github.com/netty/netty/commit/5b68c61f37aa4a3045cba624cbea239655c9003b

Details

Source: Mitre, NVD

Risk Information

CVSS v2

CVSS v3

CVSS v4

EPSS