CVE-2026-59903

Netty is an asynchronous, event-driven network application framework. Prior to 4.1.137.Final and 4.2.17.Final, io.netty.handler.codec.http.cors.CorsHandler setVaryHeader replaces application Vary headers such as Authorization or Cookie with Origin, allowing a caching proxy or CDN to reuse authenticated responses across users and disclose sensitive information. This issue is fixed in versions 4.1.137.Final and 4.2.17.Final.

CVSS v3 6.5 MEDIUM

6.5^/10

CVSS v3 : MEDIUM

Vector :

Exploitability : 2.2 / Impact : 4.2

Attack Vector NETWORK

Attack Complexity HIGH

Privileges Required NONE

User Interaction NONE

Confidentiality Impact HIGH

Integrity Impact LOW

Availability Impact NONE

Scope UNCHANGED

References

Link	Resource
https://github.com/netty/netty/pull/17213	Issue Tracking Patch
https://github.com/netty/netty/pull/17217	Issue Tracking Patch
https://github.com/netty/netty/releases/tag/netty-4.1.137.Final	Release Notes
https://github.com/netty/netty/releases/tag/netty-4.2.17.Final	Release Notes
https://github.com/netty/netty/security/advisories/GHSA-8c42-7qj2-3j46	Vendor Advisory

Configurations

Configuration 1 (hide)

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

History

23 Sep 2026, 15:21

Type	Values Removed	Values Added
References	~~() https://github.com/netty/netty/pull/17213 -~~	() https://github.com/netty/netty/pull/17213 - Issue Tracking, Patch
References	~~() https://github.com/netty/netty/pull/17217 -~~	() https://github.com/netty/netty/pull/17217 - Issue Tracking, Patch
References	~~() https://github.com/netty/netty/releases/tag/netty-4.1.137.Final -~~	() https://github.com/netty/netty/releases/tag/netty-4.1.137.Final - Release Notes
References	~~() https://github.com/netty/netty/releases/tag/netty-4.2.17.Final -~~	() https://github.com/netty/netty/releases/tag/netty-4.2.17.Final - Release Notes
References	~~() https://github.com/netty/netty/security/advisories/GHSA-8c42-7qj2-3j46 -~~	() https://github.com/netty/netty/security/advisories/GHSA-8c42-7qj2-3j46 - Vendor Advisory
CPE		cpe:2.3:a:netty:netty::::::::
First Time		Netty netty Netty

Information

Published : 2026-08-17 18:17

Updated : 2026-09-23 15:21

NVD link : CVE-2026-59903

Mitre link : CVE-2026-59903

CVE.ORG link : CVE-2026-59903

JSON object : View

Products Affected

netty

netty

CWE

CWE-524

Use of Cache Containing Sensitive Information

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