CVE-2026-42579
Published:May 13, 2026
Updated:May 18, 2026
Netty is an asynchronous, event-driven network application framework. Prior to 4.2.13.Final and 4.1.133.Final, Netty's DNS codec does not enforce RFC 1035 domain name constraints during either encoding or decoding. This creates a bidirectional attack surface: malicious DNS responses can exploit the decoder, and user-influenced hostnames can exploit the encoder. This vulnerability is fixed in 4.2.13.Final and 4.1.133.Final.
Affected Packages
https://github.com/netty/netty.git (GITHUB):
Affected version(s) >=netty-4.2.0.Alpha1 <netty-4.2.13.FinalFix Suggestion:
Update to version netty-4.2.13.Finalhttps://github.com/netty/netty.git (GITHUB):
Affected version(s) >=netty-3.2.4.Final <netty-4.1.133.FinalFix Suggestion:
Update to version netty-4.1.133.Finalio.netty:netty-codec-dns (JAVA):
Affected version(s) >=4.2.0.Alpha1 <4.2.13.FinalFix Suggestion:
Update to version 4.2.13.Finalio.netty:netty-codec-dns (JAVA):
Affected version(s) >=4.1.0.Beta1 <4.1.133.FinalFix Suggestion:
Update to version 4.1.133.Finalio.netty:netty-codec-dns (JAVA):
Affected version(s) >=4.1.0.Beta1 <4.1.133.FinalFix Suggestion:
Update to version 4.1.133.FinalRelated Resources (5)
Do you need more information?
Contact UsCVSS v4
Base Score:
8.7
Attack Vector
NETWORK
Attack Complexity
LOW
Attack Requirements
NONE
Privileges Required
NONE
User Interaction
NONE
Vulnerable System Confidentiality
NONE
Vulnerable System Integrity
HIGH
Vulnerable System Availability
NONE
Subsequent System Confidentiality
NONE
Subsequent System Integrity
NONE
Subsequent System Availability
NONE
CVSS v3
Base Score:
7.5
Attack Vector
NETWORK
Attack Complexity
LOW
Privileges Required
NONE
User Interaction
NONE
Scope
UNCHANGED
Confidentiality
NONE
Integrity
HIGH
Availability
NONE
Weakness Type (CWE)
EPSS
Base Score:
0.04