Suspicious granting of permissions to an account

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Id	b2c15736-b9eb-4dae-8b02-3016b6a45a32
Rulename	Suspicious granting of permissions to an account
Description	Identifies IPs from which users grant access to other users on Azure resources and alerts when a previously unseen source IP address is used.
Severity	Medium
Tactics	Persistence PrivilegeEscalation
Techniques	T1098 T1548
Required data connectors	AzureActivity BehaviorAnalytics
Kind	Scheduled
Query frequency	1d
Query period	14d
Trigger threshold	0
Trigger operator	gt
Source Uri	https://github.com/Azure/Azure-Sentinel/blob/master/Solutions/Azure Activity/Analytic Rules/Granting_Permissions_To_Account_detection.yaml
Version	2.0.2
Arm template	b2c15736-b9eb-4dae-8b02-3016b6a45a32.json

KQL

let starttime = 14d;
let endtime = 1d;
// The number of operations above which an IP address is considered an unusual source of role assignment operations
let alertOperationThreshold = 5;
let AzureBuiltInRole = externaldata(Role:string,RoleDescription:string,ID:string) [@"https://raw.githubusercontent.com/Azure/Azure-Sentinel/master/Sample%20Data/Feeds/AzureBuiltInRole.csv"] with (format="csv", ignoreFirstRecord=True);
let createRoleAssignmentActivity = AzureActivity
| where OperationNameValue =~ "microsoft.authorization/roleassignments/write";
let RoleAssignedActivity = createRoleAssignmentActivity 
| where TimeGenerated between (ago(starttime) .. ago(endtime))
| summarize count() by CallerIpAddress, Caller, bin(TimeGenerated, 1d)
| where count_ >= alertOperationThreshold
// Returns all the records from the right side that don't have matches from the left.
| join kind = rightanti ( 
createRoleAssignmentActivity
| where TimeGenerated > ago(endtime)
| extend parsed_property = tostring(parse_json(Properties).requestbody)
| extend PrincipalId = case(parsed_property has_cs 'PrincipalId',parse_json(parsed_property).Properties.PrincipalId, parsed_property has_cs 'principalId',parse_json(parsed_property).properties.principalId,"")
| extend PrincipalType = case(parsed_property has_cs 'PrincipalType',parse_json(parsed_property).Properties.PrincipalType, parsed_property has_cs 'principalType',parse_json(parsed_property).properties.principalType, "")
| extend Scope = case(parsed_property has_cs 'Scope',parse_json(parsed_property).Properties.Scope, parsed_property has_cs 'scope',parse_json(parsed_property).properties.scope,"")
| extend RoleAddedDetails = case(parsed_property has_cs 'RoleDefinitionId',parse_json(parsed_property).Properties.RoleDefinitionId,parsed_property has_cs 'roleDefinitionId',parse_json(parsed_property).properties.roleDefinitionId,"")
| summarize StartTimeUtc = min(TimeGenerated), EndTimeUtc = max(TimeGenerated), ActivityTimeStamp = make_set(TimeGenerated), ActivityStatusValue = make_set(ActivityStatusValue), CorrelationId = make_set(CorrelationId), ActivityCountByCallerIPAddress = count()  
by ResourceId, CallerIpAddress, Caller, OperationNameValue, Resource, ResourceGroup, PrincipalId, PrincipalType, Scope, RoleAddedDetails
) on CallerIpAddress, Caller
| extend timestamp = StartTimeUtc, AccountCustomEntity = Caller, IPCustomEntity = CallerIpAddress;
let RoleAssignedActivitywithRoleDetails = RoleAssignedActivity
| extend RoleAssignedID = tostring(split(RoleAddedDetails, "/")[-1])
// Returns all matching records from left and right sides.
| join kind = inner (AzureBuiltInRole 
) on $left.RoleAssignedID == $right.ID;
let CallerIPCountSummary = RoleAssignedActivitywithRoleDetails | summarize AssignmentCountbyCaller = count() by Caller, CallerIpAddress;
let RoleAssignedActivityWithCount = RoleAssignedActivitywithRoleDetails | join kind = inner (CallerIPCountSummary | project Caller, AssignmentCountbyCaller, CallerIpAddress) on Caller, CallerIpAddress;
RoleAssignedActivityWithCount
| summarize arg_max(StartTimeUtc, *) by PrincipalId, RoleAssignedID
// 	Returns all the records from the left side and only matching records from the right side.
| join kind = leftouter( IdentityInfo
| summarize arg_max(TimeGenerated, *) by AccountObjectId
) on $left.PrincipalId == $right.AccountObjectId
// Check if assignment count is greater than the threshold.
| where AssignmentCountbyCaller >= alertOperationThreshold
| project ActivityTimeStamp, OperationNameValue, Caller, CallerIpAddress, PrincipalId, RoleAssignedID, RoleAddedDetails, Role, RoleDescription, AccountUPN, AccountCreationTime, GroupMembership, UserType, ActivityStatusValue, ResourceGroup, PrincipalType, Scope, CorrelationId, timestamp, AccountCustomEntity, IPCustomEntity, AssignmentCountbyCaller
| extend Name = tostring(split(Caller,'@',0)[0]), UPNSuffix = tostring(split(Caller,'@',1)[0])

YAML

severity: Medium
triggerThreshold: 0
requiredDataConnectors:
- connectorId: AzureActivity
  dataTypes:
  - AzureActivity
- connectorId: BehaviorAnalytics
  dataTypes:
  - IdentityInfo
kind: Scheduled
id: b2c15736-b9eb-4dae-8b02-3016b6a45a32
triggerOperator: gt
tactics:
- Persistence
- PrivilegeEscalation
queryFrequency: 1d
OriginalUri: https://github.com/Azure/Azure-Sentinel/blob/master/Solutions/Azure Activity/Analytic Rules/Granting_Permissions_To_Account_detection.yaml
entityMappings:
- entityType: Account
  fieldMappings:
  - identifier: FullName
    columnName: Caller
  - identifier: Name
    columnName: Name
  - identifier: UPNSuffix
    columnName: UPNSuffix
- entityType: IP
  fieldMappings:
  - identifier: Address
    columnName: CallerIpAddress
relevantTechniques:
- T1098
- T1548
version: 2.0.2
queryPeriod: 14d
name: Suspicious granting of permissions to an account
status: Available
description: |
    'Identifies IPs from which users grant access to other users on Azure resources and alerts when a previously unseen source IP address is used.'
query: |
  let starttime = 14d;
  let endtime = 1d;
  // The number of operations above which an IP address is considered an unusual source of role assignment operations
  let alertOperationThreshold = 5;
  let AzureBuiltInRole = externaldata(Role:string,RoleDescription:string,ID:string) [@"https://raw.githubusercontent.com/Azure/Azure-Sentinel/master/Sample%20Data/Feeds/AzureBuiltInRole.csv"] with (format="csv", ignoreFirstRecord=True);
  let createRoleAssignmentActivity = AzureActivity
  | where OperationNameValue =~ "microsoft.authorization/roleassignments/write";
  let RoleAssignedActivity = createRoleAssignmentActivity 
  | where TimeGenerated between (ago(starttime) .. ago(endtime))
  | summarize count() by CallerIpAddress, Caller, bin(TimeGenerated, 1d)
  | where count_ >= alertOperationThreshold
  // Returns all the records from the right side that don't have matches from the left.
  | join kind = rightanti ( 
  createRoleAssignmentActivity
  | where TimeGenerated > ago(endtime)
  | extend parsed_property = tostring(parse_json(Properties).requestbody)
  | extend PrincipalId = case(parsed_property has_cs 'PrincipalId',parse_json(parsed_property).Properties.PrincipalId, parsed_property has_cs 'principalId',parse_json(parsed_property).properties.principalId,"")
  | extend PrincipalType = case(parsed_property has_cs 'PrincipalType',parse_json(parsed_property).Properties.PrincipalType, parsed_property has_cs 'principalType',parse_json(parsed_property).properties.principalType, "")
  | extend Scope = case(parsed_property has_cs 'Scope',parse_json(parsed_property).Properties.Scope, parsed_property has_cs 'scope',parse_json(parsed_property).properties.scope,"")
  | extend RoleAddedDetails = case(parsed_property has_cs 'RoleDefinitionId',parse_json(parsed_property).Properties.RoleDefinitionId,parsed_property has_cs 'roleDefinitionId',parse_json(parsed_property).properties.roleDefinitionId,"")
  | summarize StartTimeUtc = min(TimeGenerated), EndTimeUtc = max(TimeGenerated), ActivityTimeStamp = make_set(TimeGenerated), ActivityStatusValue = make_set(ActivityStatusValue), CorrelationId = make_set(CorrelationId), ActivityCountByCallerIPAddress = count()  
  by ResourceId, CallerIpAddress, Caller, OperationNameValue, Resource, ResourceGroup, PrincipalId, PrincipalType, Scope, RoleAddedDetails
  ) on CallerIpAddress, Caller
  | extend timestamp = StartTimeUtc, AccountCustomEntity = Caller, IPCustomEntity = CallerIpAddress;
  let RoleAssignedActivitywithRoleDetails = RoleAssignedActivity
  | extend RoleAssignedID = tostring(split(RoleAddedDetails, "/")[-1])
  // Returns all matching records from left and right sides.
  | join kind = inner (AzureBuiltInRole 
  ) on $left.RoleAssignedID == $right.ID;
  let CallerIPCountSummary = RoleAssignedActivitywithRoleDetails | summarize AssignmentCountbyCaller = count() by Caller, CallerIpAddress;
  let RoleAssignedActivityWithCount = RoleAssignedActivitywithRoleDetails | join kind = inner (CallerIPCountSummary | project Caller, AssignmentCountbyCaller, CallerIpAddress) on Caller, CallerIpAddress;
  RoleAssignedActivityWithCount
  | summarize arg_max(StartTimeUtc, *) by PrincipalId, RoleAssignedID
  // 	Returns all the records from the left side and only matching records from the right side.
  | join kind = leftouter( IdentityInfo
  | summarize arg_max(TimeGenerated, *) by AccountObjectId
  ) on $left.PrincipalId == $right.AccountObjectId
  // Check if assignment count is greater than the threshold.
  | where AssignmentCountbyCaller >= alertOperationThreshold
  | project ActivityTimeStamp, OperationNameValue, Caller, CallerIpAddress, PrincipalId, RoleAssignedID, RoleAddedDetails, Role, RoleDescription, AccountUPN, AccountCreationTime, GroupMembership, UserType, ActivityStatusValue, ResourceGroup, PrincipalType, Scope, CorrelationId, timestamp, AccountCustomEntity, IPCustomEntity, AssignmentCountbyCaller
  | extend Name = tostring(split(Caller,'@',0)[0]), UPNSuffix = tostring(split(Caller,'@',1)[0])

ARM

{
  "$schema": "https://schema.management.azure.com/schemas/2019-04-01/deploymentTemplate.json#",
  "contentVersion": "1.0.0.0",
  "parameters": {
    "workspace": {
      "type": "String"
    }
  },
  "resources": [
    {
      "apiVersion": "2023-02-01-preview",
      "id": "[concat(resourceId('Microsoft.OperationalInsights/workspaces/providers', parameters('workspace'), 'Microsoft.SecurityInsights'),'/alertRules/b2c15736-b9eb-4dae-8b02-3016b6a45a32')]",
      "kind": "Scheduled",
      "name": "[concat(parameters('workspace'),'/Microsoft.SecurityInsights/b2c15736-b9eb-4dae-8b02-3016b6a45a32')]",
      "properties": {
        "alertRuleTemplateName": "b2c15736-b9eb-4dae-8b02-3016b6a45a32",
        "customDetails": null,
        "description": "'Identifies IPs from which users grant access to other users on Azure resources and alerts when a previously unseen source IP address is used.'\n",
        "displayName": "Suspicious granting of permissions to an account",
        "enabled": true,
        "entityMappings": [
          {
            "entityType": "Account",
            "fieldMappings": [
              {
                "columnName": "Caller",
                "identifier": "FullName"
              },
              {
                "columnName": "Name",
                "identifier": "Name"
              },
              {
                "columnName": "UPNSuffix",
                "identifier": "UPNSuffix"
              }
            ]
          },
          {
            "entityType": "IP",
            "fieldMappings": [
              {
                "columnName": "CallerIpAddress",
                "identifier": "Address"
              }
            ]
          }
        ],
        "OriginalUri": "https://github.com/Azure/Azure-Sentinel/blob/master/Solutions/Azure Activity/Analytic Rules/Granting_Permissions_To_Account_detection.yaml",
        "query": "let starttime = 14d;\nlet endtime = 1d;\n// The number of operations above which an IP address is considered an unusual source of role assignment operations\nlet alertOperationThreshold = 5;\nlet AzureBuiltInRole = externaldata(Role:string,RoleDescription:string,ID:string) [@\"https://raw.githubusercontent.com/Azure/Azure-Sentinel/master/Sample%20Data/Feeds/AzureBuiltInRole.csv\"] with (format=\"csv\", ignoreFirstRecord=True);\nlet createRoleAssignmentActivity = AzureActivity\n| where OperationNameValue =~ \"microsoft.authorization/roleassignments/write\";\nlet RoleAssignedActivity = createRoleAssignmentActivity \n| where TimeGenerated between (ago(starttime) .. ago(endtime))\n| summarize count() by CallerIpAddress, Caller, bin(TimeGenerated, 1d)\n| where count_ >= alertOperationThreshold\n// Returns all the records from the right side that don't have matches from the left.\n| join kind = rightanti ( \ncreateRoleAssignmentActivity\n| where TimeGenerated > ago(endtime)\n| extend parsed_property = tostring(parse_json(Properties).requestbody)\n| extend PrincipalId = case(parsed_property has_cs 'PrincipalId',parse_json(parsed_property).Properties.PrincipalId, parsed_property has_cs 'principalId',parse_json(parsed_property).properties.principalId,\"\")\n| extend PrincipalType = case(parsed_property has_cs 'PrincipalType',parse_json(parsed_property).Properties.PrincipalType, parsed_property has_cs 'principalType',parse_json(parsed_property).properties.principalType, \"\")\n| extend Scope = case(parsed_property has_cs 'Scope',parse_json(parsed_property).Properties.Scope, parsed_property has_cs 'scope',parse_json(parsed_property).properties.scope,\"\")\n| extend RoleAddedDetails = case(parsed_property has_cs 'RoleDefinitionId',parse_json(parsed_property).Properties.RoleDefinitionId,parsed_property has_cs 'roleDefinitionId',parse_json(parsed_property).properties.roleDefinitionId,\"\")\n| summarize StartTimeUtc = min(TimeGenerated), EndTimeUtc = max(TimeGenerated), ActivityTimeStamp = make_set(TimeGenerated), ActivityStatusValue = make_set(ActivityStatusValue), CorrelationId = make_set(CorrelationId), ActivityCountByCallerIPAddress = count()  \nby ResourceId, CallerIpAddress, Caller, OperationNameValue, Resource, ResourceGroup, PrincipalId, PrincipalType, Scope, RoleAddedDetails\n) on CallerIpAddress, Caller\n| extend timestamp = StartTimeUtc, AccountCustomEntity = Caller, IPCustomEntity = CallerIpAddress;\nlet RoleAssignedActivitywithRoleDetails = RoleAssignedActivity\n| extend RoleAssignedID = tostring(split(RoleAddedDetails, \"/\")[-1])\n// Returns all matching records from left and right sides.\n| join kind = inner (AzureBuiltInRole \n) on $left.RoleAssignedID == $right.ID;\nlet CallerIPCountSummary = RoleAssignedActivitywithRoleDetails | summarize AssignmentCountbyCaller = count() by Caller, CallerIpAddress;\nlet RoleAssignedActivityWithCount = RoleAssignedActivitywithRoleDetails | join kind = inner (CallerIPCountSummary | project Caller, AssignmentCountbyCaller, CallerIpAddress) on Caller, CallerIpAddress;\nRoleAssignedActivityWithCount\n| summarize arg_max(StartTimeUtc, *) by PrincipalId, RoleAssignedID\n// \tReturns all the records from the left side and only matching records from the right side.\n| join kind = leftouter( IdentityInfo\n| summarize arg_max(TimeGenerated, *) by AccountObjectId\n) on $left.PrincipalId == $right.AccountObjectId\n// Check if assignment count is greater than the threshold.\n| where AssignmentCountbyCaller >= alertOperationThreshold\n| project ActivityTimeStamp, OperationNameValue, Caller, CallerIpAddress, PrincipalId, RoleAssignedID, RoleAddedDetails, Role, RoleDescription, AccountUPN, AccountCreationTime, GroupMembership, UserType, ActivityStatusValue, ResourceGroup, PrincipalType, Scope, CorrelationId, timestamp, AccountCustomEntity, IPCustomEntity, AssignmentCountbyCaller\n| extend Name = tostring(split(Caller,'@',0)[0]), UPNSuffix = tostring(split(Caller,'@',1)[0])\n",
        "queryFrequency": "P1D",
        "queryPeriod": "P14D",
        "severity": "Medium",
        "status": "Available",
        "suppressionDuration": "PT1H",
        "suppressionEnabled": false,
        "tactics": [
          "Persistence",
          "PrivilegeEscalation"
        ],
        "techniques": [
          "T1098",
          "T1548"
        ],
        "templateVersion": "2.0.2",
        "triggerOperator": "GreaterThan",
        "triggerThreshold": 0
      },
      "type": "Microsoft.OperationalInsights/workspaces/providers/alertRules"
    }
  ]
}