CVE-2026-55723

When NGINX Ingress Controller is configured with Custom Resource Definitions (CRDs) or Ingress annotations, an injection vulnerability exists in the configuration generator of NGINX Ingress Controller. Multiple user-controllable fields are written into the generated NGINX configuration without sanitization. An authenticated attacker with permission to create or modify these CRDs or annotations may craft values that inject arbitrary NGINX configuration directives. Impact: An authenticated attacker granted write access to NGINX Ingress Controller CRDs or Ingress annotations through the Kubernetes API may be able to inject arbitrary NGINX configuration directives, create or delete files, or disable services. There is no data plane exposure; this is a control plane issue only. Note: Software versions which have reached End of Technical Support (EoTS) are not evaluated.

CVSS v3 8.3 HIGH

8.3^/10

CVSS v3 : HIGH

Vector :

Exploitability : 2.8 / Impact : 5.5

Attack Vector NETWORK

Attack Complexity LOW

Privileges Required LOW

User Interaction NONE

Confidentiality Impact HIGH

Integrity Impact HIGH

Availability Impact LOW

Scope UNCHANGED

References

Link	Resource
https://my.f5.com/manage/s/article/K000161800	Mitigation Vendor Advisory

Configurations

Configuration 1 (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

16 Jul 2026, 14:02

Type	Values Removed	Values Added
References	~~() https://my.f5.com/manage/s/article/K000161800 -~~	() https://my.f5.com/manage/s/article/K000161800 - Mitigation, Vendor Advisory
First Time		F5 F5 nginx Ingress Controller
CPE		cpe:2.3:a:f5:nginx_ingress_controller::::::::

15 Jul 2026, 15:16

Type	Values Removed	Values Added
New CVE

Information

Published : 2026-07-15 15:16

Updated : 2026-07-16 14:02

NVD link : CVE-2026-55723

Mitre link : CVE-2026-55723

CVE.ORG link : CVE-2026-55723

JSON object : View

Products Affected

f5

nginx_ingress_controller

CWE

CWE-76

Improper Neutralization of Equivalent Special Elements

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