Name:Kubernetes Unauthorized Access id:9b5f1832-e8b9-453f-93df-07a3d6a72a45 version:3 date:2024-09-30 author:Patrick Bareiss, Splunk status:production type:Anomaly Description:The following analytic detects unauthorized access attempts to Kubernetes by analyzing Kubernetes audit logs. It identifies anomalies in access patterns by examining the source of requests and their response statuses. This activity is significant for a SOC as it may indicate an attacker attempting to infiltrate the Kubernetes environment. If confirmed malicious, such access could lead to unauthorized control over Kubernetes resources, potentially compromising sensitive systems or data within the cluster. Data_source:
-Kubernetes Audit
search:`kube_audit` verb=create responseStatus.reason=Forbidden | fillnull | stats count by objectRef.namespace objectRef.resource requestReceivedTimestamp requestURI responseStatus.code responseStatus.message sourceIPs{} stage user.groups{} user.uid user.username userAgent verb | rename sourceIPs{} as src_ip, user.username as user | `kubernetes_unauthorized_access_filter`
how_to_implement:The detection is based on data that originates from Kubernetes Audit logs. Ensure that audit logging is enabled in your Kubernetes cluster. Kubernetes audit logs provide a record of the requests made to the Kubernetes API server, which is crucial for monitoring and detecting suspicious activities. Configure the audit policy in Kubernetes to determine what kind of activities are logged. This is done by creating an Audit Policy and providing it to the API server. Use the Splunk OpenTelemetry Collector for Kubernetes to collect the logs. This doc will describe how to collect the audit log file https://github.com/signalfx/splunk-otel-collector-chart/blob/main/docs/migration-from-sck.md. When you want to use this detection with AWS EKS, you need to enable EKS control plane logging https://docs.aws.amazon.com/eks/latest/userguide/control-plane-logs.html. Then you can collect the logs from Cloudwatch using the AWS TA https://splunk.github.io/splunk-add-on-for-amazon-web-services/CloudWatchLogs/. known_false_positives:unknown References: -https://kubernetes.io/docs/tasks/debug/debug-cluster/audit/ drilldown_searches: name:'View the detection results for - "$user$"' search:'%original_detection_search% | search user = "$user$"' earliest_offset:'$info_min_time$' latest_offset:'$info_max_time$' name:'View risk events for the last 7 days for - "$user$"' search:'| from datamodel Risk.All_Risk | search normalized_risk_object IN ("$user$") starthoursago=168 | stats count min(_time) as firstTime max(_time) as lastTime values(search_name) as "Search Name" values(risk_message) as "Risk Message" values(analyticstories) as "Analytic Stories" values(annotations._all) as "Annotations" values(annotations.mitre_attack.mitre_tactic) as "ATT&CK Tactics" by normalized_risk_object | `security_content_ctime(firstTime)` | `security_content_ctime(lastTime)`' earliest_offset:'$info_min_time$' latest_offset:'$info_max_time$' tags: analytic_story: - 'Kubernetes Security' asset_type:Kubernetes confidence:70 impact:70 message:Unauthorized access to Kubernetes from user $user$ mitre_attack_id: - 'T1204' observable: name:'user' type:'User' - role: - 'Victim' name:'src_ip' type:'IP Address' - role: - 'Attacker' product: - 'Splunk Enterprise' - 'Splunk Enterprise Security' - 'Splunk Cloud' required_fields: - 'verb' - 'requestReceivedTimestamp' - 'requestURI' - 'responseStatus.code' - 'sourceIPs{}' - 'user.groups{}' - 'user.username' - 'userAgent' - 'verb' - 'responseStatus.reason' - 'responseStatus.status' risk_score:49 security_domain:network
