Kubernetes Role With Node Proxy Permissions Created

Severity: high
Group by: name, username
Compliance: Stratus Red Team k8s.privilege-escalation.nodes-proxy
Log types: Amazon.EKS.Audit, Azure.MonitorActivity, GCP.AuditLog
Tags: Kubernetes, Privilege Escalation, RBAC, Stratus Red Team, Unified Detection
Reference: https://stratus-red-team.cloud/attack-techniques/kubernetes/k8s.privilege-escalation.nodes-proxy/
Source: github.com/panther-labs/panther-analysis

This detection monitors for Roles or ClusterRoles being created with permissions to access node proxy endpoints (nodes/proxy or nodes/*). These permissions allow users to access the kubelet API through the Kubernetes API server proxy, enabling privilege escalation by executing commands on nodes, accessing container logs and filesystems, and potentially escaping to the underlying host. This technique is documented by Stratus Red Team as a privilege escalation vector.

MITRE ATT&CK coverage

Tactic	Techniques
Privilege Escalation	`T1078.004` Valid Accounts: Cloud Accounts
Stealth	`T1078.004` Valid Accounts: Cloud Accounts, `T1562.001` Impair Defenses: Disable or Modify Tools

Rule body yaml

AnalysisType: rule
RuleID: "Kubernetes.Role.NodeProxyPermissions"
DisplayName: "Kubernetes Role With Node Proxy Permissions Created"
Enabled: true
Filename: k8s_role_node_proxy_permissions.py
LogTypes:
  - Amazon.EKS.Audit
  - Azure.MonitorActivity
  - GCP.AuditLog
Tags:
  - Kubernetes
  - Privilege Escalation
  - RBAC
  - Stratus Red Team
  - Unified Detection
Severity: High
Description: >
  This detection monitors for Roles or ClusterRoles being created with permissions to access node proxy endpoints
  (nodes/proxy or nodes/*). These permissions allow users to access the kubelet API through the Kubernetes API server
  proxy, enabling privilege escalation by executing commands on nodes, accessing container logs and filesystems, and
  potentially escaping to the underlying host. This technique is documented by Stratus Red Team as a privilege
  escalation vector.
Runbook: |
  1. Query all RBAC operations by the username in the 2 hours before and after the alert to identify the scope of role creation activity
  2. Find all RoleBindings or ClusterRoleBindings that reference this role name in the 24 hours after creation to determine who was granted these permissions
  3. Search for API operations to nodes/proxy endpoints from the p_source_label cluster in the past 7 days to identify if these permissions have been exploited
Reports:
  Stratus Red Team:
    - k8s.privilege-escalation.nodes-proxy
  MITRE ATT&CK:
    - TA0004:T1078.004 # Privilege Escalation: Valid Accounts - Cloud Accounts
    - TA0005:T1562.001 # Defense Evasion: Impair Defenses - Disable or Modify Tools
Reference: https://stratus-red-team.cloud/attack-techniques/kubernetes/k8s.privilege-escalation.nodes-proxy/
DedupPeriodMinutes: 60
SummaryAttributes:
  - username
  - resource
  - name
  - p_source_label
Tests:
  - Name: EKS ClusterRole with nodes/proxy permission
    ExpectedResult: true
    Log:
      {
        "kind": "Event",
        "apiVersion": "audit.k8s.io/v1",
        "verb": "create",
        "user": {"username": "attacker@example.com"},
        "sourceIPs": ["203.0.113.42"],
        "userAgent": "kubectl/v1.28.0",
        "objectRef": {
          "resource": "clusterroles",
          "name": "node-accessor",
          "apiGroup": "rbac.authorization.k8s.io",
          "apiVersion": "v1"
        },
        "responseStatus": {"code": 201},
        "requestObject": {
          "kind": "ClusterRole",
          "metadata": {"name": "node-accessor"},
          "rules": [
            {
              "apiGroups": [""],
              "resources": ["nodes/proxy"],
              "verbs": ["get", "list", "create"]
            }
          ]
        },
        "p_log_type": "Amazon.EKS.Audit",
        "p_source_label": "eks-cluster"
      }
  - Name: AKS ClusterRole with nodes/* permission
    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\":\"malicious-user@example.com\"},\"sourceIPs\":[\"1.2.3.4\"],\"objectRef\":{\"resource\":\"clusterroles\",\"name\":\"node-admin\",\"apiGroup\":\"rbac.authorization.k8s.io\"},\"responseStatus\":{\"code\":201},\"requestObject\":{\"kind\":\"ClusterRole\",\"metadata\":{\"name\":\"node-admin\"},\"rules\":[{\"apiGroups\":[\"\"],\"resources\":[\"nodes/*\"],\"verbs\":[\"*\"]}]}}"
        },
        "p_source_label": "aks-cluster"
      }
  - Name: GKE ClusterRole with nodes proxy access
    ExpectedResult: true
    Log:
      {
        "protoPayload": {
          "authenticationInfo": {"principalEmail": "user@company.com"},
          "authorizationInfo": [{
            "granted": true,
            "permission": "io.k8s.rbac.v1.clusterroles.create",
            "resource": "rbac.authorization.k8s.io/v1/clusterroles/node-proxy-role"
          }],
          "methodName": "io.k8s.rbac.v1.clusterroles.create",
          "requestMetadata": {"callerIP": "8.8.8.8"},
          "resourceName": "rbac.authorization.k8s.io/v1/clusterroles/node-proxy-role",
          "serviceName": "k8s.io",
          "request": {
            "kind": "ClusterRole",
            "metadata": {"name": "node-proxy-role"},
            "rules": [
              {
                "apiGroups": [""],
                "resources": ["nodes/proxy", "nodes/log"],
                "verbs": ["get", "create"]
              }
            ]
          }
        },
        "resource": {
          "type": "k8s_cluster",
          "labels": {"project_id": "test-project"}
        },
        "p_log_type": "GCP.AuditLog",
        "p_source_label": "gke-cluster"
      }
  - Name: EKS Role with nodes wildcard
    ExpectedResult: true
    Log:
      {
        "kind": "Event",
        "verb": "create",
        "user": {"username": "suspicious-user@example.com"},
        "objectRef": {
          "resource": "clusterroles",
          "name": "node-reader",
          "apiGroup": "rbac.authorization.k8s.io"
        },
        "responseStatus": {"code": 201},
        "requestObject": {
          "kind": "ClusterRole",
          "rules": [
            {
              "apiGroups": [""],
              "resources": ["nodes", "*"],
              "verbs": ["get", "list"]
            }
          ]
        },
        "p_log_type": "Amazon.EKS.Audit",
        "p_source_label": "eks-cluster"
      }
  - Name: Role with only node list permission (no proxy)
    ExpectedResult: false
    Log:
      {
        "kind": "Event",
        "verb": "create",
        "user": {"username": "admin@example.com"},
        "objectRef": {
          "resource": "clusterroles",
          "name": "node-viewer",
          "apiGroup": "rbac.authorization.k8s.io"
        },
        "responseStatus": {"code": 201},
        "requestObject": {
          "kind": "ClusterRole",
          "rules": [
            {
              "apiGroups": [""],
              "resources": ["nodes"],
              "verbs": ["get", "list"]
            }
          ]
        },
        "p_log_type": "Amazon.EKS.Audit"
      }
  - Name: Role with pod permissions (not nodes)
    ExpectedResult: false
    Log:
      {
        "kind": "Event",
        "verb": "create",
        "user": {"username": "admin@example.com"},
        "objectRef": {
          "resource": "roles",
          "namespace": "default",
          "name": "pod-admin",
          "apiGroup": "rbac.authorization.k8s.io"
        },
        "responseStatus": {"code": 201},
        "requestObject": {
          "kind": "Role",
          "rules": [
            {
              "apiGroups": [""],
              "resources": ["pods", "pods/log"],
              "verbs": ["get", "list", "create"]
            }
          ]
        },
        "p_log_type": "Amazon.EKS.Audit"
      }
  - Name: System principal creating role (excluded)
    ExpectedResult: false
    Log:
      {
        "kind": "Event",
        "verb": "create",
        "user": {"username": "system:serviceaccount:kube-system:operator"},
        "objectRef": {
          "resource": "clusterroles",
          "name": "system-role"
        },
        "responseStatus": {"code": 201},
        "requestObject": {
          "kind": "ClusterRole",
          "rules": [
            {
              "apiGroups": [""],
              "resources": ["nodes/proxy"],
              "verbs": ["get"]
            }
          ]
        },
        "p_log_type": "Amazon.EKS.Audit"
      }
  - Name: Failed request (excluded)
    ExpectedResult: false
    Log:
      {
        "kind": "Event",
        "verb": "create",
        "user": {"username": "attacker@example.com"},
        "objectRef": {
          "resource": "clusterroles",
          "name": "node-proxy-role"
        },
        "responseStatus": {"code": 403},
        "requestObject": {
          "kind": "ClusterRole",
          "rules": [
            {
              "apiGroups": [""],
              "resources": ["nodes/proxy"],
              "verbs": ["get", "create"]
            }
          ]
        },
        "p_log_type": "Amazon.EKS.Audit"
      }
  - Name: Updating existing role (not creating)
    ExpectedResult: false
    Log:
      {
        "kind": "Event",
        "verb": "update",
        "user": {"username": "admin@example.com"},
        "objectRef": {
          "resource": "clusterroles",
          "name": "existing-role"
        },
        "responseStatus": {"code": 200},
        "requestObject": {
          "kind": "ClusterRole",
          "rules": [
            {
              "apiGroups": [""],
              "resources": ["nodes/proxy"],
              "verbs": ["get"]
            }
          ]
        },
        "p_log_type": "Amazon.EKS.Audit"
      }

Detection logic

Condition

not (verb ne "create" or resource not in ["roles", "clusterroles"])
not (responseStatus is_not_null and (responseStatus.code ge "400" or (responseStatus.code ge "1" and responseStatus.code le "16")))
not (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)
`responseStatus.code`	ge	`1`
`responseStatus.code`	le	`16`
`responseStatus.code`	ge	`400`
`responseStatus`	is_not_null	(no value, null check)
`resource`	in	`clusterroles`, `roles`
`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
`resource`	in	`clusterroles` `roles`
`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`
`name`

`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)