CVE-2026-59919

Netty is an asynchronous, event-driven network application framework. In versions prior to 4.1.136.Final and 4.2.16.Final, Netty's HAProxy encoder ( HAProxyMessageEncoder ) writes AF_UNIX source and destination socket addresses into the HAProxy V1 text protocol without validating them for CRLF characters, so an attacker who controls an AF_UNIX address can inject \r\n sequences and split the single PROXY header into multiple lines. This is possible because the V1 protocol uses CRLF as its line terminator and, unlike IPv4/IPv6 addresses whose format checks implicitly reject CRLF, AF_UNIX addresses are only validated for length (up to 108 bytes), allowing a forged second PROXY header line that spoofs the client source/destination IP to a downstream server or load balancer. The issue is fixed in versions 4.1.136.Final and 4.2.16.Final.

CVSS v3 5.5 MEDIUM

5.5^/10

CVSS v3 : MEDIUM

Vector :

Exploitability : 1.8 / Impact : 3.6

Attack Vector LOCAL

Attack Complexity LOW

Privileges Required LOW

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-wh89-7897-x99h	Exploit Vendor Advisory
https://github.com/netty/netty/security/advisories/GHSA-wh89-7897-x99h	Exploit Vendor Advisory

Configurations

Configuration 1 (hide)

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

History

06 Aug 2026, 20:33

Type	Values Removed	Values Added
First Time		Netty netty Netty
CPE		cpe:2.3:a:netty:netty::::::::
References	~~() https://github.com/netty/netty/security/advisories/GHSA-wh89-7897-x99h -~~	() https://github.com/netty/netty/security/advisories/GHSA-wh89-7897-x99h - Exploit, Vendor Advisory

29 Jul 2026, 19:16

Type	Values Removed	Values Added
References	~~() https://github.com/netty/netty/security/advisories/GHSA-wh89-7897-x99h -~~	() https://github.com/netty/netty/security/advisories/GHSA-wh89-7897-x99h -

29 Jul 2026, 18:16

Type	Values Removed	Values Added
New CVE

Information

Published : 2026-07-29 18:16

Updated : 2026-08-06 20:33

NVD link : CVE-2026-59919

Mitre link : CVE-2026-59919

CVE.ORG link : CVE-2026-59919

JSON object : View

Products Affected

netty

netty

CWE

CWE-93

Improper Neutralization of CRLF Sequences ('CRLF Injection')

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