Threat Intelligence Database

When NGINX Ingress Controller processes Ingress or TransportServer resources, an authenticated, remote attacker with permission to create or modify Ingress or TransportServer resources can cause the NGINX Ingress Controller process to terminate. Impact: The NGINX Ingress Controller control plane process terminates and enters a persistent crash loop while the malformed Ingress or TransportServer resource remains in the cluster. This vulnerability allows a remote, authenticated attacker with at least Ingress or TransportServer resource write access to cause a denial-of-service (DoS) on the NGINX Ingress Controller system. 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.

CVE-2026-55723 is an injection vulnerability in the configuration generator of F5 NGINX Ingress Controller when configured with Custom Resource Definitions (CRDs) or Ingress annotations. Authenticated users with permission to create or modify these CRDs or annotations can inject arbitrary NGINX configuration directives due to lack of sanitization of user-controllable fields. This vulnerability affects control plane operations only and does not expose the data plane. Versions 5.0.0 and 2026-lts-r1 are affected.