Kubernetes Pod with Dangerous Linux Capabilities

Severity: high
Group by: namespace, username
Log types: Amazon.EKS.Audit, Azure.MonitorActivity, GCP.AuditLog
Tags: Kubernetes, Security Control, Privilege Escalation, Container Escape, Unified Detection
Reference: - https://kubernetes.io/docs/tasks/configure-pod-container/security-context/ - https://www.dynatrace.com/news/blog/kubernetes-security-essentials-container-misconfigurations-from-theory-to-exploitation/
Source: github.com/panther-labs/panther-analysis

This detection monitors for pods created with dangerous Linux capabilities such as SYS_ADMIN, NET_ADMIN, or BPF. These capabilities can enable privilege escalation, container escape, or unauthorized access to host resources. Attackers often add these capabilities to containers to bypass security restrictions and gain elevated privileges on the underlying host.

MITRE ATT&CK coverage

Tactic	Techniques
Privilege Escalation	`T1068` Exploitation for Privilege Escalation, `T1611` Escape to Host

Rule body yaml

AnalysisType: rule
RuleID: "Kubernetes.Pod.Dangerous.Capabilities"
DisplayName: "Kubernetes Pod with Dangerous Linux Capabilities"
Enabled: true
Filename: k8s_pod_dangerous_capabilities.py
LogTypes:
  - Amazon.EKS.Audit
  - Azure.MonitorActivity
  - GCP.AuditLog
Tags:
  - Kubernetes
  - Security Control
  - Privilege Escalation
  - Container Escape
  - Unified Detection
Severity: High
Description: >
  This detection monitors for pods created with dangerous Linux capabilities such as SYS_ADMIN,
  NET_ADMIN, or BPF. These capabilities can enable privilege escalation, container escape, or
  unauthorized access to host resources. Attackers often add these capabilities to containers
  to bypass security restrictions and gain elevated privileges on the underlying host.
Runbook: |
  1. Review all pod creation events by the username in the 24 hours before the alert to determine if this is routine deployment activity
  2. Analyze the specific capabilities granted and their legitimate business justification for the workload
  3. Search for other pods with dangerous capabilities deployed by this user across all clusters in the past 30 days
Reports:
  MITRE ATT&CK:
    - TA0004:T1611 # Privilege Escalation: Escape to Host
    - TA0005:T1068 # Defense Evasion: Exploitation for Privilege Escalation
Reference: >
  - https://kubernetes.io/docs/tasks/configure-pod-container/security-context/
  - https://www.dynatrace.com/news/blog/kubernetes-security-essentials-container-misconfigurations-from-theory-to-exploitation/
DedupPeriodMinutes: 60
SummaryAttributes:
  - username
  - namespace
  - p_source_label
Tests:
  - Name: EKS Pod with SYS_ADMIN Capability
    ExpectedResult: true
    Log:
      {
        "kind": "Event",
        "apiVersion": "audit.k8s.io/v1",
        "verb": "create",
        "user": {"username": "admin@example.com"},
        "sourceIPs": ["1.2.3.4"],
        "userAgent": "kubectl/v1.28.0",
        "objectRef": {
          "resource": "pods",
          "namespace": "default",
          "name": "test-pod",
          "apiVersion": "v1"
        },
        "responseStatus": {"code": 201},
        "requestObject": {
          "kind": "Pod",
          "spec": {
            "containers": [{
              "name": "test",
              "image": "nginx",
              "securityContext": {
                "capabilities": {
                  "add": ["SYS_ADMIN", "NET_RAW"]
                }
              }
            }]
          }
        },
        "p_log_type": "Amazon.EKS.Audit",
        "p_source_label": "eks-cluster"
      }
  - Name: AKS Pod with NET_ADMIN Capability
    ExpectedResult: true
    Log:
      {
        "p_log_type": "Azure.MonitorActivity",
        "category": "kube-audit",
        "operationName": "Microsoft.ContainerService/managedClusters/diagnosticLogs/Read",
        "properties": {
          "log": "{\"kind\":\"Event\",\"apiVersion\":\"audit.k8s.io/v1\",\"verb\":\"create\",\"user\":{\"username\":\"user@example.com\"},\"sourceIPs\":[\"10.0.0.1\"],\"objectRef\":{\"resource\":\"pods\",\"namespace\":\"default\",\"name\":\"network-tool\"},\"responseStatus\":{\"code\":201},\"requestObject\":{\"spec\":{\"containers\":[{\"name\":\"net\",\"securityContext\":{\"capabilities\":{\"add\":[\"NET_ADMIN\"]}}}]}}}"
        },
        "p_source_label": "aks-cluster"
      }
  - Name: GKE Pod with BPF Capability
    ExpectedResult: true
    Log:
      {
        "protoPayload": {
          "authenticationInfo": {"principalEmail": "user@company.com"},
          "authorizationInfo": [{
            "granted": true,
            "permission": "io.k8s.core.v1.pods.create",
            "resource": "core/v1/namespaces/default/pods/monitoring"
          }],
          "methodName": "io.k8s.core.v1.pods.create",
          "requestMetadata": {"callerIP": "1.2.3.4"},
          "resourceName": "core/v1/namespaces/default/pods/monitoring",
          "serviceName": "k8s.io",
          "request": {
            "kind": "Pod",
            "spec": {
              "containers": [{
                "name": "monitor",
                "image": "bpftrace:latest",
                "securityContext": {
                  "capabilities": {
                    "add": ["BPF", "SYS_PTRACE"]
                  }
                }
              }]
            }
          }
        },
        "resource": {
          "type": "k8s_cluster",
          "labels": {"project_id": "test-project"}
        },
        "p_log_type": "GCP.AuditLog",
        "p_source_label": "gke-cluster"
      }
  - Name: Pod with Safe Capabilities Only
    ExpectedResult: false
    Log:
      {
        "kind": "Event",
        "verb": "create",
        "objectRef": {"resource": "pods", "namespace": "default"},
        "responseStatus": {"code": 201},
        "requestObject": {
          "spec": {
            "containers": [{
              "securityContext": {
                "capabilities": {
                  "add": ["NET_BIND_SERVICE", "CHOWN"]
                }
              }
            }]
          }
        },
        "p_log_type": "Amazon.EKS.Audit"
      }
  - Name: Pod without Capabilities
    ExpectedResult: false
    Log:
      {
        "kind": "Event",
        "verb": "create",
        "objectRef": {"resource": "pods", "namespace": "default"},
        "responseStatus": {"code": 201},
        "requestObject": {
          "spec": {
            "containers": [{
              "name": "app",
              "image": "nginx"
            }]
          }
        },
        "p_log_type": "Amazon.EKS.Audit"
      }
  - Name: Pod Creation Failed
    ExpectedResult: false
    Log:
      {
        "kind": "Event",
        "verb": "create",
        "objectRef": {"resource": "pods", "namespace": "default"},
        "responseStatus": {"code": 403},
        "requestObject": {
          "spec": {
            "containers": [{
              "securityContext": {
                "capabilities": {"add": ["SYS_ADMIN"]}
              }
            }]
          }
        },
        "p_log_type": "Amazon.EKS.Audit"
      }

Detection logic

Condition

not (verb ne "create" or resource ne "pods")
not (responseStatus is_not_null and (responseStatus.code ge "400" or (responseStatus.code ge "1" and responseStatus.code le "16")))
not ((namespace is_not_null and namespace in ["kube-system", "gke-system", "kube-node-lease", "kube-public"]) or (username is_not_null and (username in ["masterclient", "aksService"] or (username starts_with "system:" and username not contains "serviceaccount"))))

This rule also runs imperative logic the parser cannot express as a filter; the conditions above are the structured part it could extract.

Exclusions

Top-level NOT(...) conjuncts: predicates this rule actively suppresses.

Field	Kind	Excluded values
`username`	contains	`serviceaccount`
`username`	starts_with	`system:`
`username`	in	`aksService`, `masterclient`
`username`	is_not_null	(no value, null check)
`namespace`	in	`gke-system`, `kube-node-lease`, `kube-public`, `kube-system`
`namespace`	is_not_null	(no value, null check)
`responseStatus.code`	ge	`1`
`responseStatus.code`	le	`16`
`responseStatus.code`	ge	`400`
`responseStatus`	is_not_null	(no value, null check)
`resource`	ne	`pods`
`verb`	ne	`create`

Indicators

Each row is a field, operator, and value that the rule matches. The corpus column counts how many other rules in the catalog look for the same combination: high numbers point to widely-used, community-vetted indicators. Blank or 1 shows that the indicator is specific to this rule.

Field	Kind	Values
`username`	contains	`serviceaccount`

Output fields

Fields the rule emits when it matches. Chronicle authors list these in the outcome block; they appear on the detection and $risk_score drives alerting. Sentinel / Defender XDR rules build them up through project / summarize / extend stages. Sentinel maps these into alert fields via entityMappings and customDetails; Defender XDR custom detections surface them as alert fields directly.

Field	Source
`username`
`sourceIPs`
`userAgent`
`namespace`
`verb`
`resource`
`requestURI`
`responseStatus`
`cluster`	`p_source_label`

`j` / `k`	Scroll down / up
`d` / `u`	Half-page down / up
`gg` / `G`	Top / bottom
`h` / `l`	History back / forward
`f`	Follow link (`Shift` = new tab)
`/`	Focus search
`?`	Toggle this help
`↑` / `↓`	Navigate search results
`Enter`	Open highlighted result
`Esc`	Close results / dialog

`type:`	`events` / `rules` / `providers`
`vendor:`	`sigma` / `elastic` / `splunk` / `kusto` / `chronicle` (vendor name alone also works: `sigma:`, `kql:`, `secops:`…)
`tactic:`	TA-id, slug, or name: `credential_access`, `TA0006`
`technique:`	technique or sub-technique ID: `T1003`, `T1003.001` (alias `tech:`)
`severity:`	`critical` / `high` / `medium` / `low` / `informational` (alias `sev:`)
`risk_score`	Numeric comparison on the Elastic risk score (0 to 100): `risk_score>50`, `risk_score<=20`, `risk_score=99` (alias `risk`; Elastic rules only)
`stages:`	Rules with exactly N pipeline stages
`correlation:`	`single_event` / `sequence` / `alternatives` / `alternatives_cross_log` / `all_required` / `correlated`
`with:`	Co-occurrence event-id; stacks (`with:4624 with:4769`) to require all, while a comma list in one occurrence (`with:4624,4769`) is an either-or group. Implies multi-event
`like:`	Structural neighbors of a rule slug (equivalents + subsumption stricter / broader): `like:comsvcs_lsass_memory_dump-splunk-sysmon`
`groupby:`	Entity-grouping substring match against `group_by_keys`: `groupby:user`, `groupby:host`
`uses:`	Rules whose predicate tree touches the field (any kind, any value): `uses:CommandLine`
`excludes:`	Rules with top-level `not()` clauses on the field (FP whitelists): `excludes:ParentImage`
`field:` / `value:`	Predicate search; narrows rule cards to those with a matching leaf and drives the indicator tier. Unquoted = substring, wildcards allowed (`value:mimikatz`)
`indicator:`	Shorthand for `field:F value:V`: `indicator:Image=*\powershell.exe`
`kind:`	Filter by predicate kind. Narrows rule cards to those carrying a matching predicate leaf (`vendor:elastic kind:cidr_match`) and drives the indicator tier: `contains` / `starts_with` / `ends_with` / `regex` / `cidr` / `eq` / `in` … (operator aliases `op:`/`match:`)
`has:` / `no:`	`sample`, `field`, `notes`, `refs`, `trace`, `thirdparty`, `rule`, `pattern`, `timewindow`, `threshold`, `newterms`, `sigma`/`elastic`/`splunk`/`kusto`/`chronicle`
`-op:val`	Exclude matches; works on most operators but not `type:`/`like:`/`has:`/`no:` (use `no:<flag>` to exclude a rule flag): `tactic:execution -vendor:splunk`. Standalone `-kind:`/`-field:`/`-value:` drop every rule carrying a matching predicate leaf (`type:rules -kind:is_null`)
`field:"…"` / `value:"…"`	Quoted value = anchored exact match (also allows spaces): `value:"net user"`
`a,b`	Comma = OR inside one operator (`vendor:sigma,elastic`, `severity:high,critical`); repeating a facet merges the same way. `field:`/`value:` never split (literal commas)
`vendors:` / `stage:`	Singular and plural spellings fold to the canonical operator and value: `tactics:` = `tactic:`, `type:event` = `type:events`, `correlation:sequences` = `correlation:sequence`, `has:thresholds` = `has:threshold`
`"quoted phrase"`	Exact-match a multi-word phrase (free text)