CVE-2026-42934

NGINX Plus and NGINX Open Source have a vulnerability in the ngx_http_charset_module module. When charset, source_charset, and charset_map and proxy_pass with disabled buffering ("off") directives are configured, unauthenticated attackers can send requests that with conditions beyond the attackers' control to cause a heap buffer over-read in the NGINX worker process, leading to limited disclosure of memory or a restart. Note: Software versions which have reached End of Technical Support (EoTS) are not evaluated.

CVSS v3 4.8 MEDIUM

4.8^/10

CVSS v3 : MEDIUM

Vector :

Exploitability : 2.2 / Impact : 2.5

Attack Vector NETWORK

Attack Complexity HIGH

Privileges Required NONE

User Interaction NONE

Confidentiality Impact LOW

Integrity Impact NONE

Availability Impact LOW

Scope UNCHANGED

References

Link	Resource
https://my.f5.com/manage/s/article/K000161028	Mitigation Vendor Advisory

Configurations

Configuration 1 (hide)

OR	cpe:2.3:a:f5:dos::::::nginx::*
	cpe:2.3:a:f5:dos:4.8.0:::::nginx::
	cpe:2.3:a:f5:nginx_gateway_fabric::::::::
	cpe:2.3:a:f5:nginx_gateway_fabric::::::::
	cpe:2.3:a:f5:nginx_ingress_controller::::::::
	cpe:2.3:a:f5:nginx_ingress_controller::::::::
	cpe:2.3:a:f5:nginx_ingress_controller::::::::
	cpe:2.3:a:f5:nginx_instance_manager::::::::
	cpe:2.3:a:f5:nginx_open_source::::::::
	cpe:2.3:a:f5:nginx_open_source::::::::
	cpe:2.3:a:f5:nginx_plus::::::::
	cpe:2.3:a:f5:waf::::::nginx::*
	cpe:2.3:a:f5:waf::::::nginx::*
	cpe:2.3:a:f5:waf::::::nginx::*

History

No history.

Information

Published : 2026-05-13 16:16

Updated : 2026-06-18 14:07

NVD link : CVE-2026-42934

Mitre link : CVE-2026-42934

CVE.ORG link : CVE-2026-42934

JSON object : View

Products Affected

f5

nginx_open_source
nginx_ingress_controller
nginx_plus
waf
nginx_instance_manager
dos
nginx_gateway_fabric

CWE

CWE-125

Out-of-bounds Read

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