A critical vulnerability (CVE-2025-1974) has been identified in the Ingress-Nginx controller, a popular Kubernetes ingress controller. This vulnerability, combined with other related vulnerabilities, allows an attacker with network access to the pod network to potentially take over a Kubernetes cluster without requiring credentials or administrative access.
CVE-2025-1974 with a CVSS score of 9.8, arises from configuration injection vulnerabilities in the Validating Admission Controller feature of ingress-nginx, enabling remote code execution. By exploiting this vulnerability, an attacker can inject malicious configurations into the Nginx configuration through a specially crafted Ingress object. This allows for arbitrary command execution within the Ingress-Nginx controller pod, potentially leading to the compromise of sensitive information, including Secrets that ingress-nginx has access to. Ingress-Nginx, by default, often has access to all secrets cluster-wide.
Successful exploitation of CVE-2025-1974 could lead to complete cluster takeover. This is particularly concerning because the attack can be initiated from any entity with access to the Pod network.