KubeZero/charts/kubezero-falco/files/rules/k8s_audit_rules.yaml

805 lines
33 KiB
YAML

# SPDX-License-Identifier: Apache-2.0
#
# Copyright (C) 2023 The Falco Authors.
#
#
# Licensed under the Apache License, Version 2.0 (the "License");
# you may not use this file except in compliance with the License.
# You may obtain a copy of the License at
#
# http://www.apache.org/licenses/LICENSE-2.0
#
# Unless required by applicable law or agreed to in writing, software
# distributed under the License is distributed on an "AS IS" BASIS,
# WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
# See the License for the specific language governing permissions and
# limitations under the License.
#
- required_engine_version: 15
- required_plugin_versions:
- name: k8saudit
version: 0.7.0
alternatives:
- name: k8saudit-eks
version: 0.4.0
- name: k8saudit-gke
version: 0.1.0
- name: json
version: 0.7.0
# Like always_true/always_false, but works with k8s audit events
- macro: k8s_audit_always_true
condition: (jevt.rawtime exists)
- macro: k8s_audit_never_true
condition: (jevt.rawtime=0)
# Generally only consider audit events once the response has completed
- list: k8s_audit_stages
items: ["ResponseComplete"]
# Generally exclude users starting with "system:"
- macro: non_system_user
condition: (not ka.user.name startswith "system:")
# This macro selects the set of Audit Events used by the below rules.
- macro: kevt
condition: (jevt.value[/stage] in (k8s_audit_stages))
- macro: kevt_started
condition: (jevt.value[/stage]=ResponseStarted)
# If you wish to restrict activity to a specific set of users, override/append to this list.
# users created by kops are included
- list: vertical_pod_autoscaler_users
items: ["vpa-recommender", "vpa-updater"]
- list: allowed_k8s_users
items: [
"minikube", "minikube-user", "kubelet", "kops", "admin", "kube", "kube-proxy", "kube-apiserver-healthcheck",
"kubernetes-admin",
vertical_pod_autoscaler_users,
cluster-autoscaler,
"system:addon-manager",
"cloud-controller-manager",
"system:kube-controller-manager"
]
- list: eks_allowed_k8s_users
items: [
"eks:node-manager",
"eks:certificate-controller",
"eks:fargate-scheduler",
"eks:k8s-metrics",
"eks:authenticator",
"eks:cluster-event-watcher",
"eks:nodewatcher",
"eks:pod-identity-mutating-webhook",
"eks:cloud-controller-manager",
"eks:vpc-resource-controller",
"eks:addon-manager",
]
- list: k8s_audit_sensitive_mount_images
items: [
falcosecurity/falco, docker.io/falcosecurity/falco, public.ecr.aws/falcosecurity/falco,
docker.io/sysdig/sysdig, sysdig/sysdig,
gcr.io/google_containers/hyperkube,
gcr.io/google_containers/kube-proxy, docker.io/calico/node,
docker.io/rook/toolbox, docker.io/cloudnativelabs/kube-router, docker.io/consul,
docker.io/datadog/docker-dd-agent, docker.io/datadog/agent, docker.io/docker/ucp-agent, docker.io/gliderlabs/logspout,
docker.io/netdata/netdata, docker.io/google/cadvisor, docker.io/prom/node-exporter,
amazon/amazon-ecs-agent, prom/node-exporter, amazon/cloudwatch-agent
]
- list: k8s_audit_privileged_images
items: [
falcosecurity/falco, docker.io/falcosecurity/falco, public.ecr.aws/falcosecurity/falco,
docker.io/calico/node, calico/node,
docker.io/cloudnativelabs/kube-router,
docker.io/docker/ucp-agent,
docker.io/mesosphere/mesos-slave,
docker.io/rook/toolbox,
docker.io/sysdig/sysdig,
gcr.io/google_containers/kube-proxy,
gcr.io/google-containers/startup-script,
gcr.io/projectcalico-org/node,
gke.gcr.io/kube-proxy,
gke.gcr.io/gke-metadata-server,
gke.gcr.io/netd-amd64,
gke.gcr.io/watcher-daemonset,
gcr.io/google-containers/prometheus-to-sd,
registry.k8s.io/ip-masq-agent-amd64,
registry.k8s.io/kube-proxy,
registry.k8s.io/prometheus-to-sd,
quay.io/calico/node,
sysdig/sysdig,
registry.k8s.io/dns/k8s-dns-node-cache,
mcr.microsoft.com/oss/kubernetes/kube-proxy
]
- rule: Disallowed K8s User
desc: Detect any k8s operation by users outside of an allowed set of users.
condition: kevt and non_system_user and not ka.user.name in (allowed_k8s_users) and not ka.user.name in (eks_allowed_k8s_users)
output: K8s Operation performed by user not in allowed list of users (user=%ka.user.name target=%ka.target.name/%ka.target.resource verb=%ka.verb uri=%ka.uri resp=%ka.response.code)
priority: WARNING
source: k8s_audit
tags: [k8s]
# In a local/user rules file, you could override this macro to
# explicitly enumerate the container images that you want to run in
# your environment. In this main falco rules file, there isn't any way
# to know all the containers that can run, so any container is
# allowed, by using the always_true macro. In the overridden macro, the condition
# would look something like (ka.req.pod.containers.image.repository in (my-repo/my-image))
- macro: allowed_k8s_containers
condition: (k8s_audit_always_true)
- macro: response_successful
condition: (ka.response.code startswith 2)
- macro: kget
condition: ka.verb=get
- macro: kcreate
condition: ka.verb=create
- macro: kmodify
condition: (ka.verb in (create,update,patch))
- macro: kdelete
condition: ka.verb=delete
- macro: pod
condition: ka.target.resource=pods and not ka.target.subresource exists
- macro: pod_subresource
condition: ka.target.resource=pods and ka.target.subresource exists
- macro: deployment
condition: ka.target.resource=deployments
- macro: service
condition: ka.target.resource=services
- macro: configmap
condition: ka.target.resource=configmaps
- macro: namespace
condition: ka.target.resource=namespaces
- macro: serviceaccount
condition: ka.target.resource=serviceaccounts
- macro: clusterrole
condition: ka.target.resource=clusterroles
- macro: clusterrolebinding
condition: ka.target.resource=clusterrolebindings
- macro: role
condition: ka.target.resource=roles
- macro: secret
condition: ka.target.resource=secrets
- macro: health_endpoint
condition: ka.uri=/healthz or ka.uri startswith /healthz?
- macro: live_endpoint
condition: ka.uri=/livez or ka.uri startswith /livez?
- macro: ready_endpoint
condition: ka.uri=/readyz or ka.uri startswith /readyz?
- rule: Create Disallowed Pod
desc: >
Detect an attempt to start a pod with a container image outside of a list of allowed images.
condition: kevt and pod and kcreate and not allowed_k8s_containers
output: Pod started with container not in allowed list (user=%ka.user.name pod=%ka.resp.name ns=%ka.target.namespace images=%ka.req.pod.containers.image)
priority: WARNING
source: k8s_audit
tags: [k8s]
- rule: Create Privileged Pod
desc: >
Detect an attempt to start a pod with a privileged container
condition: kevt and pod and kcreate and ka.req.pod.containers.privileged intersects (true) and not ka.req.pod.containers.image.repository in (k8s_audit_privileged_images)
output: Pod started with privileged container (user=%ka.user.name pod=%ka.resp.name resource=%ka.target.resource ns=%ka.target.namespace images=%ka.req.pod.containers.image)
priority: WARNING
source: k8s_audit
tags: [k8s]
- macro: sensitive_vol_mount
condition: >
(ka.req.pod.volumes.hostpath intersects (/proc, /var/run/docker.sock, /, /etc, /root, /var/run/crio/crio.sock, /run/containerd/containerd.sock, /home/admin, /var/lib/kubelet, /var/lib/kubelet/pki, /etc/kubernetes, /etc/kubernetes/manifests))
- rule: Create Sensitive Mount Pod
desc: >
Detect an attempt to start a pod with a volume from a sensitive host directory (i.e. /proc).
Exceptions are made for known trusted images.
condition: kevt and pod and kcreate and sensitive_vol_mount and not ka.req.pod.containers.image.repository in (k8s_audit_sensitive_mount_images)
output: Pod started with sensitive mount (user=%ka.user.name pod=%ka.resp.name ns=%ka.target.namespace resource=%ka.target.resource images=%ka.req.pod.containers.image volumes=%jevt.value[/requestObject/spec/volumes])
priority: WARNING
source: k8s_audit
tags: [k8s]
# These container images are allowed to run with hostnetwork=true
# TODO: Remove k8s.gcr.io reference after 01/Dec/2023
- list: k8s_audit_hostnetwork_images
items: [
gcr.io/google-containers/prometheus-to-sd,
gcr.io/projectcalico-org/typha,
gcr.io/projectcalico-org/node,
gke.gcr.io/gke-metadata-server,
gke.gcr.io/kube-proxy,
gke.gcr.io/netd-amd64,
registry.k8s.io/ip-masq-agent-amd64,
registry.k8s.io/prometheus-to-sd
]
# Corresponds to K8s CIS Benchmark 1.7.4
- rule: Create HostNetwork Pod
desc: Detect an attempt to start a pod using the host network.
condition: kevt and pod and kcreate and ka.req.pod.host_network intersects (true) and not ka.req.pod.containers.image.repository in (k8s_audit_hostnetwork_images)
output: Pod started using host network (user=%ka.user.name pod=%ka.resp.name resource=%ka.target.resource ns=%ka.target.namespace images=%ka.req.pod.containers.image)
priority: WARNING
source: k8s_audit
tags: [k8s]
- list: k8s_audit_hostpid_images
items: []
- rule: Create HostPid Pod
desc: Detect an attempt to start a pod using the host pid namespace.
condition: kevt and pod and kcreate and ka.req.pod.host_pid intersects (true) and not ka.req.pod.containers.image.repository in (k8s_audit_hostpid_images)
output: Pod started using host pid namespace (user=%ka.user.name pod=%ka.resp.name resource=%ka.target.resource ns=%ka.target.namespace images=%ka.req.pod.containers.image)
priority: WARNING
source: k8s_audit
tags: [k8s]
- list: k8s_audit_hostipc_images
items: []
- rule: Create HostIPC Pod
desc: Detect an attempt to start a pod using the host ipc namespace.
condition: kevt and pod and kcreate and ka.req.pod.host_ipc intersects (true) and not ka.req.pod.containers.image.repository in (k8s_audit_hostipc_images)
output: Pod started using host ipc namespace (user=%ka.user.name pod=%ka.resp.name resource=%ka.target.resource ns=%ka.target.namespace images=%ka.req.pod.containers.image)
priority: WARNING
source: k8s_audit
tags: [k8s]
- macro: user_known_node_port_service
condition: (k8s_audit_never_true)
- rule: Create NodePort Service
desc: >
Detect an attempt to start a service with a NodePort service type
condition: kevt and service and kcreate and ka.req.service.type=NodePort and not user_known_node_port_service
output: NodePort Service Created (user=%ka.user.name service=%ka.target.name resource=%ka.target.resource ns=%ka.target.namespace ports=%ka.req.service.ports)
priority: WARNING
source: k8s_audit
tags: [k8s]
- macro: contains_private_credentials
condition: >
(ka.req.configmap.obj contains "aws_access_key_id" or
ka.req.configmap.obj contains "aws-access-key-id" or
ka.req.configmap.obj contains "aws_s3_access_key_id" or
ka.req.configmap.obj contains "aws-s3-access-key-id" or
ka.req.configmap.obj contains "password" or
ka.req.configmap.obj contains "passphrase")
- rule: Create/Modify Configmap With Private Credentials
desc: >
Detect creating/modifying a configmap containing a private credential (aws key, password, etc.)
condition: kevt and configmap and kmodify and contains_private_credentials
output: K8s configmap with private credential (user=%ka.user.name verb=%ka.verb resource=%ka.target.resource configmap=%ka.req.configmap.name config=%ka.req.configmap.obj)
priority: WARNING
source: k8s_audit
tags: [k8s]
# Corresponds to K8s CIS Benchmark, 1.1.1.
- rule: Anonymous Request Allowed
desc: >
Detect any request made by the anonymous user that was allowed
condition: kevt and ka.user.name=system:anonymous and ka.auth.decision="allow" and not health_endpoint and not live_endpoint and not ready_endpoint
output: Request by anonymous user allowed (user=%ka.user.name verb=%ka.verb uri=%ka.uri reason=%ka.auth.reason))
priority: WARNING
source: k8s_audit
tags: [k8s]
# Roughly corresponds to K8s CIS Benchmark, 1.1.12. In this case,
# notifies an attempt to exec/attach to a privileged container.
# Ideally, we'd add a more stringent rule that detects attaches/execs
# to a privileged pod, but that requires the engine for k8s audit
# events to be stateful, so it could know if a container named in an
# attach request was created privileged or not. For now, we have a
# less severe rule that detects attaches/execs to any pod.
#
# For the same reason, you can't use things like image names/prefixes,
# as the event that creates the pod (which has the images) is a
# separate event than the actual exec/attach to the pod.
- macro: user_known_exec_pod_activities
condition: (k8s_audit_never_true)
- rule: Attach/Exec Pod
desc: >
Detect any attempt to attach/exec to a pod
condition: kevt_started and pod_subresource and kcreate and ka.target.subresource in (exec,attach) and not user_known_exec_pod_activities
output: Attach/Exec to pod (user=%ka.user.name pod=%ka.target.name resource=%ka.target.resource ns=%ka.target.namespace action=%ka.target.subresource command=%ka.uri.param[command])
priority: NOTICE
source: k8s_audit
tags: [k8s]
- macro: user_known_portforward_activities
condition: (k8s_audit_never_true)
- rule: port-forward
desc: >
Detect any attempt to portforward
condition: ka.target.subresource in (portforward) and not user_known_portforward_activities
output: Portforward to pod (user=%ka.user.name pod=%ka.target.name ns=%ka.target.namespace action=%ka.target.subresource )
priority: NOTICE
source: k8s_audit
tags: [k8s]
- macro: user_known_pod_debug_activities
condition: (k8s_audit_never_true)
# Only works when feature gate EphemeralContainers is enabled
- rule: EphemeralContainers Created
desc: >
Detect any ephemeral container created
condition: kevt and pod_subresource and kmodify and ka.target.subresource in (ephemeralcontainers) and not user_known_pod_debug_activities
output: Ephemeral container is created in pod (user=%ka.user.name pod=%ka.target.name resource=%ka.target.resource ns=%ka.target.namespace ephemeral_container_name=%jevt.value[/requestObject/ephemeralContainers/0/name] ephemeral_container_image=%jevt.value[/requestObject/ephemeralContainers/0/image])
priority: NOTICE
source: k8s_audit
tags: [k8s]
# In a local/user rules fie, you can append to this list to add additional allowed namespaces
- list: allowed_namespaces
items: [kube-system, kube-public, default]
- rule: Create Disallowed Namespace
desc: Detect any attempt to create a namespace outside of a set of known namespaces
condition: kevt and namespace and kcreate and not ka.target.name in (allowed_namespaces)
output: Disallowed namespace created (user=%ka.user.name ns=%ka.target.name resource=%ka.target.resource)
priority: WARNING
source: k8s_audit
tags: [k8s]
# Only defined for backwards compatibility. Use the more specific
# user_allowed_kube_namespace_image_list instead.
- list: user_trusted_image_list
items: []
- list: user_allowed_kube_namespace_image_list
items: [user_trusted_image_list]
# Only defined for backwards compatibility. Use the more specific
# allowed_kube_namespace_image_list instead.
- list: k8s_image_list
items: []
# TODO: Remove k8s.gcr.io reference after 01/Dec/2023
- list: allowed_kube_namespace_image_list
items: [
gcr.io/google-containers/prometheus-to-sd,
gcr.io/projectcalico-org/node,
gke.gcr.io/addon-resizer,
gke.gcr.io/heapster,
gke.gcr.io/gke-metadata-server,
registry.k8s.io/ip-masq-agent-amd64,
registry.k8s.io/kube-apiserver,
gke.gcr.io/kube-proxy,
gke.gcr.io/netd-amd64,
gke.gcr.io/watcher-daemonset,
registry.k8s.io/addon-resizer,
registry.k8s.io/prometheus-to-sd,
registry.k8s.io/k8s-dns-dnsmasq-nanny-amd64,
registry.k8s.io/k8s-dns-kube-dns-amd64,
registry.k8s.io/k8s-dns-sidecar-amd64,
registry.k8s.io/metrics-server-amd64,
kope/kube-apiserver-healthcheck,
k8s_image_list
]
- macro: allowed_kube_namespace_pods
condition: (ka.req.pod.containers.image.repository in (user_allowed_kube_namespace_image_list) or
ka.req.pod.containers.image.repository in (allowed_kube_namespace_image_list))
# Detect any new pod created in the kube-system namespace
- rule: Pod Created in Kube Namespace
desc: Detect any attempt to create a pod in the kube-system or kube-public namespaces
condition: kevt and pod and kcreate and ka.target.namespace in (kube-system, kube-public) and not allowed_kube_namespace_pods
output: Pod created in kube namespace (user=%ka.user.name pod=%ka.resp.name resource=%ka.target.resource ns=%ka.target.namespace images=%ka.req.pod.containers.image)
priority: WARNING
source: k8s_audit
tags: [k8s]
- list: user_known_sa_list
items: []
- list: known_sa_list
items: [
coredns,
coredns-autoscaler,
cronjob-controller,
daemon-set-controller,
deployment-controller,
disruption-controller,
endpoint-controller,
endpointslice-controller,
endpointslicemirroring-controller,
generic-garbage-collector,
horizontal-pod-autoscaler,
job-controller,
namespace-controller,
node-controller,
persistent-volume-binder,
pod-garbage-collector,
pv-protection-controller,
pvc-protection-controller,
replicaset-controller,
resourcequota-controller,
root-ca-cert-publisher,
service-account-controller,
statefulset-controller
]
- macro: trusted_sa
condition: (ka.target.name in (known_sa_list, user_known_sa_list))
# Detect creating a service account in the kube-system/kube-public namespace
- rule: Service Account Created in Kube Namespace
desc: Detect any attempt to create a serviceaccount in the kube-system or kube-public namespaces
condition: kevt and serviceaccount and kcreate and ka.target.namespace in (kube-system, kube-public) and response_successful and not trusted_sa
output: Service account created in kube namespace (user=%ka.user.name serviceaccount=%ka.target.name resource=%ka.target.resource ns=%ka.target.namespace)
priority: WARNING
source: k8s_audit
tags: [k8s]
# Detect any modify/delete to any ClusterRole starting with
# "system:". "system:coredns" is excluded as changes are expected in
# normal operation.
- rule: System ClusterRole Modified/Deleted
desc: Detect any attempt to modify/delete a ClusterRole/Role starting with system
condition: kevt and (role or clusterrole) and (kmodify or kdelete) and (ka.target.name startswith "system:") and
not ka.target.name in (system:coredns, system:managed-certificate-controller)
output: System ClusterRole/Role modified or deleted (user=%ka.user.name role=%ka.target.name resource=%ka.target.resource ns=%ka.target.namespace action=%ka.verb)
priority: WARNING
source: k8s_audit
tags: [k8s]
# Detect any attempt to create a ClusterRoleBinding to the cluster-admin user
# (expand this to any built-in cluster role that does "sensitive" things)
- rule: Attach to cluster-admin Role
desc: Detect any attempt to create a ClusterRoleBinding to the cluster-admin user
condition: kevt and clusterrolebinding and kcreate and ka.req.binding.role=cluster-admin
output: Cluster Role Binding to cluster-admin role (user=%ka.user.name subject=%ka.req.binding.subjects)
priority: WARNING
source: k8s_audit
tags: [k8s]
- rule: ClusterRole With Wildcard Created
desc: Detect any attempt to create a Role/ClusterRole with wildcard resources or verbs
condition: kevt and (role or clusterrole) and kcreate and (ka.req.role.rules.resources intersects ("*") or ka.req.role.rules.verbs intersects ("*"))
output: Created Role/ClusterRole with wildcard (user=%ka.user.name role=%ka.target.name resource=%ka.target.resource rules=%ka.req.role.rules)
priority: WARNING
source: k8s_audit
tags: [k8s]
- macro: writable_verbs
condition: >
(ka.req.role.rules.verbs intersects (create, update, patch, delete, deletecollection))
- rule: ClusterRole With Write Privileges Created
desc: Detect any attempt to create a Role/ClusterRole that can perform write-related actions
condition: kevt and (role or clusterrole) and kcreate and writable_verbs
output: Created Role/ClusterRole with write privileges (user=%ka.user.name role=%ka.target.name resource=%ka.target.resource rules=%ka.req.role.rules)
priority: NOTICE
source: k8s_audit
tags: [k8s]
- rule: ClusterRole With Pod Exec Created
desc: Detect any attempt to create a Role/ClusterRole that can exec to pods
condition: kevt and (role or clusterrole) and kcreate and ka.req.role.rules.resources intersects ("pods/exec")
output: Created Role/ClusterRole with pod exec privileges (user=%ka.user.name role=%ka.target.name resource=%ka.target.resource rules=%ka.req.role.rules)
priority: WARNING
source: k8s_audit
tags: [k8s]
# The rules below this point are less discriminatory and generally
# represent a stream of activity for a cluster. If you wish to disable
# these events, modify the following macro.
- macro: consider_activity_events
condition: (k8s_audit_always_true)
- macro: kactivity
condition: (kevt and consider_activity_events)
- rule: K8s Deployment Created
desc: Detect any attempt to create a deployment
condition: (kactivity and kcreate and deployment and response_successful)
output: K8s Deployment Created (user=%ka.user.name deployment=%ka.target.name ns=%ka.target.namespace resource=%ka.target.resource resp=%ka.response.code decision=%ka.auth.decision reason=%ka.auth.reason)
priority: INFO
source: k8s_audit
tags: [k8s]
- rule: K8s Deployment Deleted
desc: Detect any attempt to delete a deployment
condition: (kactivity and kdelete and deployment and response_successful)
output: K8s Deployment Deleted (user=%ka.user.name deployment=%ka.target.name ns=%ka.target.namespace resource=%ka.target.resource resp=%ka.response.code decision=%ka.auth.decision reason=%ka.auth.reason)
priority: INFO
source: k8s_audit
tags: [k8s]
- rule: K8s Service Created
desc: Detect any attempt to create a service
condition: (kactivity and kcreate and service and response_successful)
output: K8s Service Created (user=%ka.user.name service=%ka.target.name ns=%ka.target.namespace resource=%ka.target.resource resp=%ka.response.code decision=%ka.auth.decision reason=%ka.auth.reason)
priority: INFO
source: k8s_audit
tags: [k8s]
- rule: K8s Service Deleted
desc: Detect any attempt to delete a service
condition: (kactivity and kdelete and service and response_successful)
output: K8s Service Deleted (user=%ka.user.name service=%ka.target.name ns=%ka.target.namespace resource=%ka.target.resource resp=%ka.response.code decision=%ka.auth.decision reason=%ka.auth.reason)
priority: INFO
source: k8s_audit
tags: [k8s]
- rule: K8s ConfigMap Created
desc: Detect any attempt to create a configmap
condition: (kactivity and kcreate and configmap and response_successful)
output: K8s ConfigMap Created (user=%ka.user.name configmap=%ka.target.name ns=%ka.target.namespace resource=%ka.target.resource resp=%ka.response.code decision=%ka.auth.decision reason=%ka.auth.reason)
priority: INFO
source: k8s_audit
tags: [k8s]
- rule: K8s ConfigMap Deleted
desc: Detect any attempt to delete a configmap
condition: (kactivity and kdelete and configmap and response_successful)
output: K8s ConfigMap Deleted (user=%ka.user.name configmap=%ka.target.name ns=%ka.target.namespace resource=%ka.target.resource resp=%ka.response.code decision=%ka.auth.decision reason=%ka.auth.reason)
priority: INFO
source: k8s_audit
tags: [k8s]
- rule: K8s Namespace Created
desc: Detect any attempt to create a namespace
condition: (kactivity and kcreate and namespace and response_successful)
output: K8s Namespace Created (user=%ka.user.name namespace=%ka.target.name resource=%ka.target.resource resp=%ka.response.code decision=%ka.auth.decision reason=%ka.auth.reason)
priority: INFO
source: k8s_audit
tags: [k8s]
- rule: K8s Namespace Deleted
desc: Detect any attempt to delete a namespace
condition: (kactivity and non_system_user and kdelete and namespace and response_successful)
output: K8s Namespace Deleted (user=%ka.user.name namespace=%ka.target.name resource=%ka.target.resource resp=%ka.response.code decision=%ka.auth.decision reason=%ka.auth.reason)
priority: INFO
source: k8s_audit
tags: [k8s]
- rule: K8s Serviceaccount Created
desc: Detect any attempt to create a service account
condition: (kactivity and kcreate and serviceaccount and response_successful)
output: K8s Serviceaccount Created (user=%ka.user.name serviceaccount=%ka.target.name ns=%ka.target.namespace resource=%ka.target.resource resp=%ka.response.code decision=%ka.auth.decision reason=%ka.auth.reason)
priority: INFO
source: k8s_audit
tags: [k8s]
- rule: K8s Serviceaccount Deleted
desc: Detect any attempt to delete a service account
condition: (kactivity and kdelete and serviceaccount and response_successful)
output: K8s Serviceaccount Deleted (user=%ka.user.name serviceaccount=%ka.target.name ns=%ka.target.namespace resource=%ka.target.resource resp=%ka.response.code decision=%ka.auth.decision reason=%ka.auth.reason)
priority: INFO
source: k8s_audit
tags: [k8s]
- rule: K8s Role/Clusterrole Created
desc: Detect any attempt to create a cluster role/role
condition: (kactivity and kcreate and (clusterrole or role) and response_successful)
output: K8s Cluster Role Created (user=%ka.user.name role=%ka.target.name resource=%ka.target.resource rules=%ka.req.role.rules resp=%ka.response.code decision=%ka.auth.decision reason=%ka.auth.reason)
priority: INFO
source: k8s_audit
tags: [k8s]
- rule: K8s Role/Clusterrole Deleted
desc: Detect any attempt to delete a cluster role/role
condition: (kactivity and kdelete and (clusterrole or role) and response_successful)
output: K8s Cluster Role Deleted (user=%ka.user.name role=%ka.target.name resource=%ka.target.resource resp=%ka.response.code decision=%ka.auth.decision reason=%ka.auth.reason)
priority: INFO
source: k8s_audit
tags: [k8s]
- rule: K8s Role/Clusterrolebinding Created
desc: Detect any attempt to create a clusterrolebinding
condition: (kactivity and kcreate and clusterrolebinding and response_successful)
output: K8s Cluster Role Binding Created (user=%ka.user.name binding=%ka.target.name resource=%ka.target.resource subjects=%ka.req.binding.subjects role=%ka.req.binding.role resp=%ka.response.code decision=%ka.auth.decision reason=%ka.auth.reason)
priority: INFO
source: k8s_audit
tags: [k8s]
- rule: K8s Role/Clusterrolebinding Deleted
desc: Detect any attempt to delete a clusterrolebinding
condition: (kactivity and kdelete and clusterrolebinding and response_successful)
output: K8s Cluster Role Binding Deleted (user=%ka.user.name binding=%ka.target.name resource=%ka.target.resource resp=%ka.response.code decision=%ka.auth.decision reason=%ka.auth.reason)
priority: INFO
source: k8s_audit
tags: [k8s]
- rule: K8s Secret Created
desc: Detect any attempt to create a secret. Service account tokens are excluded.
condition: (kactivity and kcreate and secret and ka.target.namespace!=kube-system and non_system_user and response_successful)
output: K8s Secret Created (user=%ka.user.name secret=%ka.target.name ns=%ka.target.namespace resource=%ka.target.resource resp=%ka.response.code decision=%ka.auth.decision reason=%ka.auth.reason)
priority: INFO
source: k8s_audit
tags: [k8s]
- rule: K8s Secret Deleted
desc: Detect any attempt to delete a secret. Service account tokens are excluded.
condition: (kactivity and kdelete and secret and ka.target.namespace!=kube-system and non_system_user and response_successful)
output: K8s Secret Deleted (user=%ka.user.name secret=%ka.target.name ns=%ka.target.namespace resource=%ka.target.resource resp=%ka.response.code decision=%ka.auth.decision reason=%ka.auth.reason)
priority: INFO
source: k8s_audit
tags: [k8s]
- rule: K8s Secret Get Successfully
desc: >
Detect any attempt to get a secret. Service account tokens are excluded.
condition: >
secret and kget
and kactivity
and response_successful
output: K8s Secret Get Successfully (user=%ka.user.name secret=%ka.target.name ns=%ka.target.namespace resource=%ka.target.resource resp=%ka.response.code decision=%ka.auth.decision reason=%ka.auth.reason)
priority: ERROR
source: k8s_audit
tags: [k8s]
- rule: K8s Secret Get Unsuccessfully Tried
desc: >
Detect an unsuccessful attempt to get the secret. Service account tokens are excluded.
condition: >
secret and kget
and kactivity
and not response_successful
output: K8s Secret Get Unsuccessfully Tried (user=%ka.user.name secret=%ka.target.name ns=%ka.target.namespace resource=%ka.target.resource resp=%ka.response.code decision=%ka.auth.decision reason=%ka.auth.reason)
priority: WARNING
source: k8s_audit
tags: [k8s]
# This rule generally matches all events, and as a result is disabled
# by default. If you wish to enable these events, modify the
# following macro.
# condition: (jevt.rawtime exists)
- macro: consider_all_events
condition: (k8s_audit_never_true)
- macro: kall
condition: (kevt and consider_all_events)
- rule: All K8s Audit Events
desc: Match all K8s Audit Events
condition: kall
output: K8s Audit Event received (user=%ka.user.name verb=%ka.verb uri=%ka.uri obj=%jevt.obj)
priority: DEBUG
source: k8s_audit
tags: [k8s]
# This macro disables following rule, change to k8s_audit_never_true to enable it
- macro: allowed_full_admin_users
condition: (k8s_audit_always_true)
# This list includes some of the default user names for an administrator in several K8s installations
- list: full_admin_k8s_users
items: ["admin", "kubernetes-admin", "kubernetes-admin@kubernetes", "kubernetes-admin@cluster.local", "minikube-user"]
# This rules detect an operation triggered by an user name that is
# included in the list of those that are default administrators upon
# cluster creation. This may signify a permission setting too broader.
# As we can't check for role of the user on a general ka.* event, this
# may or may not be an administrator. Customize the full_admin_k8s_users
# list to your needs, and activate at your discretion.
# # How to test:
# # Execute any kubectl command connected using default cluster user, as:
# kubectl create namespace rule-test
- rule: Full K8s Administrative Access
desc: Detect any k8s operation by a user name that may be an administrator with full access.
condition: >
kevt
and non_system_user
and ka.user.name in (full_admin_k8s_users)
and not allowed_full_admin_users
output: K8s Operation performed by full admin user (user=%ka.user.name target=%ka.target.name/%ka.target.resource verb=%ka.verb uri=%ka.uri resp=%ka.response.code)
priority: WARNING
source: k8s_audit
tags: [k8s]
- macro: ingress
condition: ka.target.resource=ingresses
- macro: ingress_tls
condition: (jevt.value[/requestObject/spec/tls] exists)
# # How to test:
# # Create an ingress.yaml file with content:
# apiVersion: networking.k8s.io/v1beta1
# kind: Ingress
# metadata:
# name: test-ingress
# annotations:
# nginx.ingress.kubernetes.io/rewrite-target: /
# spec:
# rules:
# - http:
# paths:
# - path: /testpath
# backend:
# serviceName: test
# servicePort: 80
# # Execute: kubectl apply -f ingress.yaml
- rule: Ingress Object without TLS Certificate Created
desc: Detect any attempt to create an ingress without TLS certification.
condition: >
(kactivity and kcreate and ingress and response_successful and not ingress_tls)
output: >
K8s Ingress Without TLS Cert Created (user=%ka.user.name ingress=%ka.target.name
namespace=%ka.target.namespace resource=%ka.target.resource)
source: k8s_audit
priority: WARNING
tags: [k8s, network]
- macro: node
condition: ka.target.resource=nodes
- macro: allow_all_k8s_nodes
condition: (k8s_audit_always_true)
- list: allowed_k8s_nodes
items: []
# # How to test:
# # Create a Falco monitored cluster with Kops
# # Increase the number of minimum nodes with:
# kops edit ig nodes
# kops apply --yes
- rule: Untrusted Node Successfully Joined the Cluster
desc: >
Detect a node successfully joined the cluster outside of the list of allowed nodes.
condition: >
kevt and node
and kcreate
and response_successful
and not allow_all_k8s_nodes
and not ka.target.name in (allowed_k8s_nodes)
output: Node not in allowed list successfully joined the cluster (user=%ka.user.name node=%ka.target.name resource=%ka.target.resource)
priority: ERROR
source: k8s_audit
tags: [k8s]
- rule: Untrusted Node Unsuccessfully Tried to Join the Cluster
desc: >
Detect an unsuccessful attempt to join the cluster for a node not in the list of allowed nodes.
condition: >
kevt and node
and kcreate
and not response_successful
and not allow_all_k8s_nodes
and not ka.target.name in (allowed_k8s_nodes)
output: Node not in allowed list tried unsuccessfully to join the cluster (user=%ka.user.name node=%ka.target.name reason=%ka.response.reason resource=%ka.target.resource)
priority: WARNING
source: k8s_audit
tags: [k8s]