Kubernetes Pod created with a Sensitive hostPath Volume
editKubernetes Pod created with a Sensitive hostPath Volume
editThis rule detects when a pod is created with a sensitive volume of type hostPath. A hostPath volume type mounts a sensitive file or folder from the node to the container. If the container gets compromised, the attacker can use this mount for gaining access to the node. There are many ways a container with unrestricted access to the host filesystem can escalate privileges, including reading data from other containers, and accessing tokens of more privileged pods.
Rule type: query
Rule indices:
- logs-kubernetes.*
Severity: medium
Risk score: 47
Runs every: 5 minutes
Searches indices from: now-6m (Date Math format, see also Additional look-back time)
Maximum alerts per execution: 100
References:
Tags:
- Elastic
- Kubernetes
- Continuous Monitoring
- Execution
- Privilege Escalation
Version: 200 (version history)
Added (Elastic Stack release): 8.4.0
Last modified (Elastic Stack release): 8.6.0
Rule authors: Elastic
Rule license: Elastic License v2
Potential false positives
editAn administrator may need to attach a hostPath volume for a legitimate reason. This alert should be investigated for legitimacy by determining if the kuberenetes.audit.requestObject.spec.volumes.hostPath.path triggered is one needed by its target container/pod. For example, when the fleet managed elastic agent is deployed as a daemonset it creates several hostPath volume mounts, some of which are sensitive host directories like /proc, /etc/kubernetes, and /var/log. Add exceptions for trusted container images using the query field "kubernetes.audit.requestObject.spec.container.image"
Investigation guide
editRule query
editevent.dataset : "kubernetes.audit_logs" and
kubernetes.audit.annotations.authorization_k8s_io/decision:"allow"
and kubernetes.audit.objectRef.resource:"pods" and
kubernetes.audit.verb:("create" or "update" or "patch") and
kubernetes.audit.requestObject.spec.volumes.hostPath.path: ("/" or
"/proc" or "/root" or "/var" or "/var/run" or
"/var/run/docker.sock" or "/var/run/crio/crio.sock" or
"/var/run/cri-dockerd.sock" or "/var/lib/kubelet" or
"/var/lib/kubelet/pki" or "/var/lib/docker/overlay2" or "/etc"
or "/etc/kubernetes" or "/etc/kubernetes/manifests" or
"/etc/kubernetes/pki" or "/home/admin") and not
kubernetes.audit.requestObject.spec.containers.image:
("docker.elastic.co/beats/elastic-agent:8.4.0")
Threat mapping
editFramework: MITRE ATT&CKTM
-
Tactic:
- Name: Privilege Escalation
- ID: TA0004
- Reference URL: https://attack.mitre.org/tactics/TA0004/
-
Technique:
- Name: Escape to Host
- ID: T1611
- Reference URL: https://attack.mitre.org/techniques/T1611/
-
Tactic:
- Name: Execution
- ID: TA0002
- Reference URL: https://attack.mitre.org/tactics/TA0002/
-
Technique:
- Name: Deploy Container
- ID: T1610
- Reference URL: https://attack.mitre.org/techniques/T1610/
Rule version history
edit- Version 200 (8.6.0 release)
-
-
Updated query, changed from:
kubernetes.audit.objectRef.resource:"pods" and kubernetes.audit.verb:("create" or "update" or "patch") and kubernetes.audit.requestObject.spec.volumes.hostPath.path:("/" or "/proc" or "/root" or "/var" or "/var/run/docker.sock" or "/var/run/crio/crio.sock" or "/var/run/cri-dockerd.sock" or "/var/lib/kubelet" or "/var/lib/kubelet/pki" or "/var/lib/docker/overlay2" or "/etc" or "/etc/kubernetes" or "/etc/kubernetes/manifests" or "/home/admin")
-
- Version 100 (8.5.0 release)
-
-
Updated query, changed from:
kubernetes.audit.objectRef.resource:"pods" and kubernetes.audit.verb:("create" or "update" or "patch") and kubernetes.audit.requestObject.spec.volumes.hostPath.path:("/" or "/proc" or "/root" or "/var" or "/var/run/docker.sock" or "/var/run/crio/crio.sock" or "/var/run/cri-dockerd.sock" or "/var/lib/kubelet" or "/var/lib/kubelet/pki" or "/var/lib/docker/overlay2" or "/etc" or "/etc/kubernetes" or "/etc/kubernetes/manifests" or "/home/admin")
-