CVE-2026-42926

When NGINX Open Source is configured to proxy HTTP/2 traffic by setting proxy_http_version to 2, and also uses proxy_set_body, an attacker may be able to inject frame headers and payload bytes to the upstream peer. Note: Software versions which have reached End of Technical Support (EoTS) are not evaluated.

CVSS v3 5.8 MEDIUM

5.8^/10

CVSS v3 : MEDIUM

Vector :

Exploitability : 3.9 / Impact : 1.4

Attack Vector NETWORK

Attack Complexity LOW

Privileges Required NONE

User Interaction NONE

Confidentiality Impact NONE

Integrity Impact LOW

Availability Impact NONE

Scope CHANGED

References

Link	Resource
https://my.f5.com/manage/s/article/K000161131	Mitigation Vendor Advisory

Configurations

Configuration 1 (hide)

OR	cpe:2.3:a:f5:nginx_gateway_fabric::::::::
	cpe:2.3:a:f5:nginx_open_source::::::::

Configuration 2 (hide)

OR	cpe:2.3:a:f5:nginx_gateway_fabric::::::::
	cpe:2.3:a:f5:nginx_instance_manager::::::::

Configuration 3 (hide)

OR	cpe:2.3:a:f5:nginx_ingress_controller::::::::
	cpe:2.3:a:f5:nginx_ingress_controller::::::::
	cpe:2.3:a:f5:nginx_ingress_controller::::::::

History

18 Jun 2026, 13:37

Type	Values Removed	Values Added
CPE		cpe:2.3:a:f5:nginx_instance_manager:::::::: cpe:2.3:a:f5:nginx_open_source:::::::: cpe:2.3:a:f5:nginx_gateway_fabric:::::::: cpe:2.3:a:f5:nginx_ingress_controller::::::::
References	~~() https://my.f5.com/manage/s/article/K000161131 -~~	() https://my.f5.com/manage/s/article/K000161131 - Mitigation, Vendor Advisory
First Time		F5 nginx Gateway Fabric F5 nginx Open Source F5 nginx Ingress Controller F5 nginx Instance Manager F5

13 May 2026, 16:27

Type	Values Removed	Values Added
New CVE

Information

Published : 2026-05-13 16:16

Updated : 2026-06-18 13:37

NVD link : CVE-2026-42926

Mitre link : CVE-2026-42926

CVE.ORG link : CVE-2026-42926

JSON object : View

Products Affected

f5

nginx_ingress_controller
nginx_gateway_fabric
nginx_instance_manager
nginx_open_source

CWE

CWE-172

Encoding Error

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