Back to overview

CVE-2026-56817

HIGH
8.3
CVSS 4.0
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.

Metadata

CVE ID
CVE-2026-56817
State
PUBLISHED
Assigner
GitHub_M
Reserved
2026-06-23 14:55 UTC
Published
2026-07-21 22:06 UTC
Last updated
2026-07-22 15:42 UTC
Primary CWE
CWE-611
CWE-611: Improper Restriction of XML External Entity Referen…
Vendor / Product
netty / netty
Sources
cve.org  ·  NVD

Severity & Metrics

8.3 HIGH CVSS 4.0
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
SSVC — CISA Coordinator
Exploitation
none
Automatable
yes
Tech. Impact
partial
Affected products (1)
VendorProductPlatformVersions
netty netty — >= 4.2.0.Final, < 4.2.16.Final, >= 4.1.0.Final, < 4.1.136.Final
Weakness (CWE)
CWESourceDescription
CWE-611 cna CWE-611: Improper Restriction of XML External Entity Reference
CVSS scores (1)
ScoreSeverityVersionSourceVector
8.3 HIGH 4.0 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
References (5)
Back to overview