Detection rules › Panther

GCP Permissions Granted to Create or Manage Service Account Key

Severity
low
Entities
emails, ip_addresses
Log types
GCP.AuditLog
Reference
https://cloud.google.com/iam/docs/keys-create-delete
Source
github.com/panther-labs/panther-analysis

Permissions granted to impersonate a service account. This includes predefined service account IAM roles granted at the parent project, folder or organization-level.

Rule body yaml

AnalysisType: rule
Description: Permissions granted to impersonate a service account. This includes predefined service account IAM roles granted at the parent project, folder or organization-level.
DisplayName: GCP Permissions Granted to Create or Manage Service Account Key
Enabled: true
Filename: gcp_permissions_granted_to_create_or_manage_service_account_key.py
Reference: https://cloud.google.com/iam/docs/keys-create-delete
Severity: Low
Tests:
  - ExpectedResult: false
    Log:
      insertid: abcdefghijklmn
      logname: projects/gcp-project1/logs/cloudaudit.googleapis.com%2Factivity
      operation:
        id: 1234567890123-gcp-project1:abcdefghijklmnopqrstuvwz
        last: true
        producer: bigquery.googleapis.com
      p_any_emails:
        - user@company.io
      p_any_ip_addresses:
        - 1.2.3.4
      p_event_time: "2023-03-28 18:37:06.079"
      p_log_type: GCP.AuditLog
      p_parse_time: "2023-03-28 18:38:14.478"
      p_row_id: 06bf03d9d5dfbadba981899e1787bf05
      p_schema_version: 0
      p_source_id: 964c7894-9a0d-4ddf-864f-0193438221d6
      p_source_label: gcp-logsource
      protoPayload:
        at_sign_type: type.googleapis.com/google.cloud.audit.AuditLog
        authenticationInfo:
          principalEmail: user@company.io
        authorizationInfo:
          - granted: true
            permission: bigquery.tables.delete
            resource: projects/gcp-project1/datasets/test1/tables/newtable
        metadata:
          "@type": type.googleapis.com/google.cloud.audit.BigQueryAuditMetadata
          methodName: google.cloud.bigquery.v2.JobService.InsertJob
          requestMetadata:
            callerIP: 1.2.3.4
            callerSuppliedUserAgent: Mozilla/5.0 (Macintosh; Intel Mac OS X 10_15_7) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/111.0.0.0 Safari/537.36,gzip(gfe),gzip(gfe)
          resourceName: projects/gcp-project1/datasets/test1/tables/newtable
          serviceName: bigquery.googleapis.com
          status: {}
          tableDeletion:
            jobName: projects/gcp-project1/jobs/bquxjob_5e4a0679_18729a639d7
            reason: QUERY
        receivetimestamp: "2023-03-28 18:37:06.745"
        resource:
          labels:
            dataset_id: test1
            project_id: gcp-project1
          type: bigquery_dataset
        severity: NOTICE
        timestamp: "2023-03-28 18:37:06.079"
    Name: other event
  - ExpectedResult: true
    Log:
      insertId: hhpfjvdgakc
      logName: projects/gcp-project1/logs/cloudaudit.googleapis.com%2Factivity
      p_any_emails:
        - user@company.io
      p_any_ip_addresses:
        - 1.2.3.4
      p_event_time: "2023-04-10 18:36:30.838"
      p_log_type: GCP.AuditLog
      p_parse_time: "2023-04-10 18:38:14.607"
      p_row_id: 5286b52d4095c9f1b2e8eabe178f8203
      p_schema_version: 0
      p_source_id: 5b77391b-afad-46c7-8ddc-b8e21d4726b3
      p_source_label: gcplogsource2
      protoPayload:
        at_sign_type: type.googleapis.com/google.cloud.audit.AuditLog
        authenticationInfo:
          principalEmail: user@company.io
          principalSubject: user:user@company.io
        authorizationInfo:
          - granted: true
            permission: iam.serviceAccounts.setIamPolicy
            resource: projects/-/serviceAccounts/105537103139416651075
            resourceAttributes:
              name: projects/-/serviceAccounts/105537103139416651075
        methodName: google.iam.admin.v1.SetIAMPolicy
        request:
          "@type": type.googleapis.com/google.iam.v1.SetIamPolicyRequest
          policy:
            bindings:
              - members:
                  - serviceAccount:test-account3@gcp-project1.iam.gserviceaccount.com
                role: roles/iam.serviceAccountTokenCreator
              - members:
                  - serviceAccount:test-account3@gcp-project1.iam.gserviceaccount.com
                role: roles/iam.serviceAccountUser
            etag: ACAB
            version: 3
          resource: projects/gcp-project1/serviceAccounts/105537103139416651075
        requestMetadata:
          callerIP: 1.2.3.4
          callerSuppliedUserAgent: Mozilla/5.0 (Macintosh; Intel Mac OS X 10_15_7) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/111.0.0.0 Safari/537.36,gzip(gfe)
          destinationAttributes: {}
          requestAttributes:
            auth: {}
            time: "2023-04-10T18:36:30.994141642Z"
        resourceName: projects/-/serviceAccounts/105537103139416651075
        response:
          "@type": type.googleapis.com/google.iam.v1.Policy
          bindings:
            - members:
                - serviceAccount:test-account3@gcp-project1.iam.gserviceaccount.com
              role: roles/iam.serviceAccountTokenCreator
            - members:
                - serviceAccount:test-account3@gcp-project1.iam.gserviceaccount.com
              role: roles/iam.serviceAccountUser
          etag: BwX4/6dQjX4=
          version: 1
        serviceData:
          "@type": type.googleapis.com/google.iam.v1.logging.AuditData
          policyDelta:
            bindingDeltas:
              - action: ADD
                member: serviceAccount:test-account3@gcp-project1.iam.gserviceaccount.com
                role: roles/iam.serviceAccountTokenCreator
              - action: ADD
                member: serviceAccount:test-account3@gcp-project1.iam.gserviceaccount.com
                role: roles/iam.serviceAccountUser
        serviceName: iam.googleapis.com
        status: {}
      receiveTimestamp: "2023-04-10 18:36:32.268"
      resource:
        labels:
          email_id: test-account3@gcp-project1.iam.gserviceaccount.com
          project_id: gcp-project1
          unique_id: "105537103139416651075"
        type: service_account
      severity: NOTICE
      timestamp: "2023-04-10 18:36:30.838"
    Name: service account match
DedupPeriodMinutes: 60
LogTypes:
  - GCP.AuditLog
RuleID: GCP.Permissions.Granted.to.Create.or.Manage.Service.Account.Key
Threshold: 1

Detection logic

Condition

protoPayload.methodName contains "SetIAMPolicy"
protoPayload.serviceData.policyDelta.bindingDeltas.role in ["roles/iam.serviceAccountTokenCreator", "roles/iam.serviceAccountUser"]
protoPayload.serviceData.policyDelta.bindingDeltas.action eq "ADD"

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.

FieldKindValues
protoPayload.methodNamecontains
  • SetIAMPolicy
protoPayload.serviceData.policyDelta.bindingDeltas.actioneq
  • ADD
protoPayload.serviceData.policyDelta.bindingDeltas.rolein
  • roles/iam.serviceAccountTokenCreator
  • roles/iam.serviceAccountUser

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.

FieldSource
resource
serviceDataprotoPayload.serviceData
principalEmailprotoPayload.authenticationInfo.principalEmail
email_idresource.labels.email_id