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.
Affected products
netty: netty
References5
- github.com/netty/netty/security/advisories/GHSA-4qhr-g3c6-fcfx Vendor Advisory
- github.com/netty/netty/commit/5b68c61f37aa4a3045cba624cbea23965… Patch
- github.com/netty/netty/commit/bb2ff68a1fb71cb4b0eb9a9e17b66c52a… Patch
- github.com/netty/netty/releases/tag/netty-4.1.136.Final Release Notes
- github.com/netty/netty/releases/tag/netty-4.2.16.Final Release Notes
Metrics
- CVSS 3.1
-
9.8
CRITICAL
Score source: NVD
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H - CVSS 4.0
-
8.3
HIGH
Score source: CNA
CVSS:4.0/AV:N/AC:L/AT:P/PR:N/UI:N/VC:H/VI:N/VA:L/SC:N/SI:N/SA:N/E:X/CR:X/IR:X/AR:X/MAV:X/MAC:X/MAT:X/MPR:X/MUI:X/MVC:X/MVI:X/MVA:X/MSC:X/MSI:X/MSA:X/S:X/AU:X/R:X/V:X/RE:X/U:X - EPSS — exploit probability
- 1% percentile: 54 · as of 14 November 2026
- CWE
- CWE-611
Could this be exploited in your environment?
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