CVE-2026-42579

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.

CVSS v3 7.5 HIGH

7.5^/10

CVSS v3 : HIGH

Vector :

Exploitability : 3.9 / Impact : 3.6

Attack Vector NETWORK

Attack Complexity LOW

Privileges Required NONE

User Interaction NONE

Confidentiality Impact NONE

Integrity Impact HIGH

Availability Impact NONE

Scope UNCHANGED

References

Link	Resource
https://github.com/netty/netty/security/advisories/GHSA-cm33-6792-r9fm	Exploit Mitigation Vendor Advisory
https://github.com/netty/netty/security/advisories/GHSA-cm33-6792-r9fm	Exploit Mitigation Vendor Advisory

Configurations

Configuration 1 (hide)

OR	cpe:2.3:a:netty:netty::::::::
	cpe:2.3:a:netty:netty::::::::

History

18 May 2026, 17:16

Type	Values Removed	Values Added
References	~~() https://github.com/netty/netty/security/advisories/GHSA-cm33-6792-r9fm - Exploit, Mitigation, Vendor Advisory~~	() https://github.com/netty/netty/security/advisories/GHSA-cm33-6792-r9fm - Exploit, Mitigation, Vendor Advisory

18 May 2026, 12:48

Type	Values Removed	Values Added
First Time		Netty netty Netty
References	~~() https://github.com/netty/netty/security/advisories/GHSA-cm33-6792-r9fm -~~	() https://github.com/netty/netty/security/advisories/GHSA-cm33-6792-r9fm - Exploit, Mitigation, Vendor Advisory
CPE		cpe:2.3:a:netty:netty::::::::

13 May 2026, 19:17

Type	Values Removed	Values Added
New CVE

Information

Published : 2026-05-13 19:17

Updated : 2026-05-18 17:16

NVD link : CVE-2026-42579

Mitre link : CVE-2026-42579

CVE.ORG link : CVE-2026-42579

JSON object : View

Products Affected

netty

netty

CWE

CWE-20

Improper Input Validation

CWE-400

Uncontrolled Resource Consumption

CWE-626

Null Byte Interaction Error (Poison Null Byte)

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