XML External Entity (XXE) Injection Affecting netty package, versions *


Severity

Recommended
0.0
critical
0
10

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Threat Intelligence

EPSS
0.37% (30th percentile)

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  • Snyk IDSNYK-ECHOLATEST-NETTY-18234896
  • published23 Jul 2026
  • disclosed21 Jul 2026

Introduced: 21 Jul 2026

NewCVE-2026-56817  (opens in a new tab)
CWE-611  (opens in a new tab)

How to fix?

There is no fixed version for Echo:latest netty.

NVD Description

Note: Versions mentioned in the description apply only to the upstream netty package and not the netty package as distributed by Echo. See How to fix? for Echo:latest relevant fixed versions and status.

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.

CVSS Base Scores

version 3.1