ingress-nginx mirror-target self-DOS

A security issue was discovered in ingress-nginx where a user with permission to create an Ingress may be able to cause denial of service of the ingress-nginx data plane, or possibly redirect traffic from other Ingresses. Kubernetes clusters are only affected if they are using ingress-nginx. Due to a missing check, the mirror-target Ingress annotation can be used to target an unauthenticated configuration API within the ingress-nginx controller, allowing write commands to be submitted. Corrupting the data within that configuration API results in all traffic through ingress-nginx being dropped until an Ingress configuration change or a controller restart causes the data to be recreated correctly. In principle, this write access could also be used to redirect traffic from other Ingresses controlled by the same ingress-nginx instance. In practice, there is negligible additional risk: such redirection would require privileged information about internal ingress-nginx state, and users can already redirect traffic from other Ingresses controlled by the same ingress-nginx anyway.

ingress-nginx comment-based nginx configuration injection

A security issue was discovered in ingress-nginx where a combination of Ingress annotations can be used to inject configuration into nginx. This can lead to arbitrary code execution in the context of the ingress-nginx controller, and disclosure of Secrets accessible to the controller. (Note that in the default installation, the controller can access all Secrets cluster-wide.)

ingress-nginx rewrite-target nginx configuration injection

A security issue was discovered in ingress-nginx where the `nginx.ingress.kubernetes.io/rewrite-target` Ingress annotation can be used to inject configuration into nginx. This can lead to arbitrary code execution in the context of the ingress-nginx controller, and disclosure of Secrets accessible to the controller. (Note that in the default installation, the controller can access all Secrets cluster-wide.)

ingress-nginx auth-method nginx configuration injection

A security issue was discovered in ingress-nginx where the `nginx.ingress.kubernetes.io/auth-method` Ingress annotation can be used to inject configuration into nginx. This can lead to arbitrary code execution in the context of the ingress-nginx controller, and disclosure of Secrets accessible to the controller. (Note that in the default installation, the controller can access all Secrets cluster-wide.)

ingress-nginx auth-url protection bypass

A security issue was discovered in ingress-nginx where the protection afforded by the `auth-url` Ingress annotation may not be effective in the presence of a specific misconfiguration. If the ingress-nginx controller is configured with a default custom-errors configuration that includes HTTP errors 401 or 403, and if the configured default custom-errors backend is defective and fails to respect the X-Code HTTP header, then an Ingress with the `auth-url` annotation may be accessed even when authentication fails. Note that the built-in custom-errors backend works correctly. To trigger this issue requires an administrator to specifically configure ingress-nginx with a broken external component.

ingress-nginx Admission Controller denial of service

A security issue was discovered in ingress-nginx where the validating admission controller feature is subject to a denial of service condition. By sending large requests to the validating admission controller, an attacker can cause memory consumption, which may result in the ingress-nginx controller pod being killed or the node running out of memory.

ingress-nginx auth-method nginx configuration injection

A security issue was discovered in ingress-nginx where the `rules.http.paths.path` Ingress field can be used to inject configuration into nginx. This can lead to arbitrary code execution in the context of the ingress-nginx controller, and disclosure of Secrets accessible to the controller. (Note that in the default installation, the controller can access all Secrets cluster-wide.)

ingress-nginx auth-proxy-set-headers nginx configuration injection

A security issue was discovered in ingress-nginx where the `nginx.ingress.kubernetes.io/auth-proxy-set-headers` Ingress annotation can be used to inject configuration into nginx. This can lead to arbitrary code execution in the context of the ingress-nginx controller, and disclosure of Secrets accessible to the controller. (Note that in the default installation, the controller can access all Secrets cluster-wide.)

A security issue was discovered in ingress-nginx where an actor with permission to create Ingress objects (in the `networking.k8s.io` or `extensions` API group) can bypass annotation validation to inject arbitrary commands and obtain the credentials of the ingress-nginx controller. In the default configuration, that credential has access to all secrets in the cluster.

ingress-nginx controller - configuration injection via unsanitized auth-tls-match-cn annotation

A security issue was discovered in ingress-nginx https://github.com/kubernetes/ingress-nginx where the `auth-tls-match-cn` Ingress annotation can be used to inject configuration into nginx. This can lead to arbitrary code execution in the context of the ingress-nginx controller, and disclosure of Secrets accessible to the controller. (Note that in the default installation, the controller can access all Secrets cluster-wide.)

ingress-nginx controller - configuration injection via unsanitized mirror annotations

A security issue was discovered in ingress-nginx https://github.com/kubernetes/ingress-nginx where the `mirror-target` and `mirror-host` Ingress annotations can be used to inject arbitrary configuration into nginx. This can lead to arbitrary code execution in the context of the ingress-nginx controller, and disclosure of Secrets accessible to the controller. (Note that in the default installation, the controller can access all Secrets cluster-wide.)

ingress-nginx admission controller RCE escalation

A security issue was discovered in Kubernetes where under certain conditions, an unauthenticated attacker with access to the pod network can achieve arbitrary code execution in the context of the ingress-nginx controller. This can lead to disclosure of Secrets accessible to the controller. (Note that in the default installation, the controller can access all Secrets cluster-wide.)

ingress-nginx controller - auth secret file path traversal vulnerability

A security issue was discovered in ingress-nginx https://github.com/kubernetes/ingress-nginx where attacker-provided data are included in a filename by the ingress-nginx Admission Controller feature, resulting in directory traversal within the container. This could result in denial of service, or when combined with other vulnerabilities, limited disclosure of Secret objects from the cluster.

ingress-nginx controller - configuration injection via unsanitized auth-url annotation

A security issue was discovered in ingress-nginx https://github.com/kubernetes/ingress-nginx where the `auth-url` Ingress annotation can be used to inject configuration into nginx. This can lead to arbitrary code execution in the context of the ingress-nginx controller, and disclosure of Secrets accessible to the controller. (Note that in the default installation, the controller can access all Secrets cluster-wide.)

Code injection via nginx.ingress.kubernetes.io/permanent-redirect annotation

Code injection via nginx.ingress.kubernetes.io/permanent-redirect annotation.

Ingress nginx annotation injection causes arbitrary command execution

Ingress nginx annotation injection causes arbitrary command execution.

Ingress-nginx `path` sanitization can be bypassed with `log_format` directive

Ingress-nginx `path` sanitization can be bypassed with `log_format` directive.

Ingress-nginx `path` sanitization can be bypassed with newline character

A security issue was discovered in ingress-nginx where a user that can create or update ingress objects can use a newline character to bypass the sanitization of the `spec.rules[].http.paths[].path` field of an Ingress object (in the `networking.k8s.io` or `extensions` API group) to obtain the credentials of the ingress-nginx controller. In the default configuration, that credential has access to all secrets in the cluster.

Ingress-nginx directive injection via annotations

A security issue was discovered in ingress-nginx where a user that can create or update ingress objects can use .metadata.annotations in an Ingress object (in the networking.k8s.io or extensions API group) to obtain the credentials of the ingress-nginx controller. In the default configuration, that credential has access to all secrets in the cluster.

Ingress-nginx path can be pointed to service account token file

A security issue was discovered in ingress-nginx where a user that can create or update ingress objects can use the spec.rules[].http.paths[].path field of an Ingress object (in the networking.k8s.io or extensions API group) to obtain the credentials of the ingress-nginx controller. In the default configuration, that credential has access to all secrets in the cluster.