Suspicious granting of permissions to an account

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])

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])  
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.'
triggerOperator: gt
triggerThreshold: 0
queryPeriod: 14d
queryFrequency: 1d
entityMappings:
- entityType: Account
  fieldMappings:
  - columnName: Caller
    identifier: FullName
  - columnName: Name
    identifier: Name
  - columnName: UPNSuffix
    identifier: UPNSuffix
- entityType: IP
  fieldMappings:
  - columnName: CallerIpAddress
    identifier: Address
name: Suspicious granting of permissions to an account
status: Available
id: b2c15736-b9eb-4dae-8b02-3016b6a45a32
tactics:
- Persistence
- PrivilegeEscalation
kind: Scheduled
requiredDataConnectors:
- connectorId: AzureActivity
  dataTypes:
  - AzureActivity
- connectorId: BehaviorAnalytics
  dataTypes:
  - IdentityInfo
OriginalUri: https://github.com/Azure/Azure-Sentinel/blob/master/Solutions/Azure Activity/Analytic Rules/Granting_Permissions_To_Account_detection.yaml
version: 2.0.2
severity: Medium
relevantTechniques:
- T1098
- T1548