Application Redirect URL Update

AuditLogs
  | where Category =~ "ApplicationManagement"
  | where Result =~ "success"
  | where OperationName =~ 'Update Application'
  | where TargetResources has "AppAddress"
  | mv-expand TargetResources
  | mv-expand TargetResources.modifiedProperties
  | where TargetResources_modifiedProperties.displayName =~ "AppAddress"
  | extend Key = tostring(TargetResources_modifiedProperties.displayName)
  | extend NewValue = TargetResources_modifiedProperties.newValue
  | extend OldValue = TargetResources_modifiedProperties.oldValue
  | where isnotempty(Key) and isnotempty(NewValue)
  | project-reorder Key, NewValue, OldValue
  | extend NewUrls = extract_all('"Address":([^,]*)', tostring(NewValue))
  | extend OldUrls = extract_all('"Address":([^,]*)', tostring(OldValue))
  | extend AddedUrls = set_difference(NewUrls, OldUrls)
  | where array_length(AddedUrls) > 0
  | extend UserAgent = iif(tostring(AdditionalDetails[0].key) == "User-Agent", tostring(AdditionalDetails[0].value), "")
  | extend InitiatingAppName = tostring(InitiatedBy.app.displayName)
  | extend InitiatingAppServicePrincipalId = tostring(InitiatedBy.app.servicePrincipalId)
  | extend InitiatingUserPrincipalName = tostring(InitiatedBy.user.userPrincipalName)
  | extend InitiatingAadUserId = tostring(InitiatedBy.user.id)
  | extend InitiatingIPAddress = tostring(InitiatedBy.user.ipAddress)
  | extend AddedBy = iif(isnotempty(InitiatingUserPrincipalName), InitiatingUserPrincipalName, InitiatingAppName)
  | extend TargetAppName = tostring(TargetResources.displayName)
  | extend InitiatingAccountName = tostring(split(InitiatingUserPrincipalName, "@")[0]), InitiatingAccountUPNSuffix = tostring(split(InitiatingUserPrincipalName, "@")[1])
  | project-reorder TimeGenerated, TargetAppName, InitiatingAppName, InitiatingAppServicePrincipalId, InitiatingUserPrincipalName, InitiatingAadUserId, InitiatingIPAddress, AddedUrls, AddedBy, UserAgent

metadata:
  source:
    kind: Community
  author:
    name: Microsoft Security Research
  categories:
    domains:
    - Security - Others
  support:
    tier: Community
relevantTechniques:
- T1078.004
queryFrequency: 1d
description: |
  'Detects the redirect URL of an app being changed.
    Applications associated with URLs not controlled by the organization can pose a security risk.
    Ref: https://docs.microsoft.com/azure/active-directory/fundamentals/security-operations-applications#application-configuration-changes'  
severity: Medium
entityMappings:
- fieldMappings:
  - identifier: Url
    columnName: AddedUrls
  entityType: URL
- fieldMappings:
  - identifier: FullName
    columnName: InitiatingUserPrincipalName
  - identifier: Name
    columnName: InitiatingAccountName
  - identifier: UPNSuffix
    columnName: InitiatingAccountUPNSuffix
  entityType: Account
- fieldMappings:
  - identifier: AadUserId
    columnName: InitiatingAadUserId
  entityType: Account
- fieldMappings:
  - identifier: AadUserId
    columnName: InitiatingAppServicePrincipalId
  entityType: Account
- fieldMappings:
  - identifier: Address
    columnName: InitiatingIPAddress
  entityType: IP
triggerThreshold: 0
tactics:
- Persistence
- PrivilegeEscalation
requiredDataConnectors:
- dataTypes:
  - AuditLogs
  connectorId: AzureActiveDirectory
tags:
- AADSecOpsGuide
queryPeriod: 1d
id: a1080fc1-13d1-479b-8340-255f0290d96c
triggerOperator: gt
query: |
  AuditLogs
    | where Category =~ "ApplicationManagement"
    | where Result =~ "success"
    | where OperationName =~ 'Update Application'
    | where TargetResources has "AppAddress"
    | mv-expand TargetResources
    | mv-expand TargetResources.modifiedProperties
    | where TargetResources_modifiedProperties.displayName =~ "AppAddress"
    | extend Key = tostring(TargetResources_modifiedProperties.displayName)
    | extend NewValue = TargetResources_modifiedProperties.newValue
    | extend OldValue = TargetResources_modifiedProperties.oldValue
    | where isnotempty(Key) and isnotempty(NewValue)
    | project-reorder Key, NewValue, OldValue
    | extend NewUrls = extract_all('"Address":([^,]*)', tostring(NewValue))
    | extend OldUrls = extract_all('"Address":([^,]*)', tostring(OldValue))
    | extend AddedUrls = set_difference(NewUrls, OldUrls)
    | where array_length(AddedUrls) > 0
    | extend UserAgent = iif(tostring(AdditionalDetails[0].key) == "User-Agent", tostring(AdditionalDetails[0].value), "")
    | extend InitiatingAppName = tostring(InitiatedBy.app.displayName)
    | extend InitiatingAppServicePrincipalId = tostring(InitiatedBy.app.servicePrincipalId)
    | extend InitiatingUserPrincipalName = tostring(InitiatedBy.user.userPrincipalName)
    | extend InitiatingAadUserId = tostring(InitiatedBy.user.id)
    | extend InitiatingIPAddress = tostring(InitiatedBy.user.ipAddress)
    | extend AddedBy = iif(isnotempty(InitiatingUserPrincipalName), InitiatingUserPrincipalName, InitiatingAppName)
    | extend TargetAppName = tostring(TargetResources.displayName)
    | extend InitiatingAccountName = tostring(split(InitiatingUserPrincipalName, "@")[0]), InitiatingAccountUPNSuffix = tostring(split(InitiatingUserPrincipalName, "@")[1])
    | project-reorder TimeGenerated, TargetAppName, InitiatingAppName, InitiatingAppServicePrincipalId, InitiatingUserPrincipalName, InitiatingAadUserId, InitiatingIPAddress, AddedUrls, AddedBy, UserAgent  
name: Application Redirect URL Update
version: 1.1.1
kind: Scheduled
OriginalUri: https://github.com/Azure/Azure-Sentinel/blob/master/Detections/AuditLogs/ApplicationRedirectURLUpdate.yaml