OAuth application redirect URI modified

id: 32cf350a-01f8-4c84-9e47-4302e275eda3
name: OAuth application redirect URI modified
description: Identifies modifications to OAuth application redirect URIs in Entra ID. Adding a redirect URI controlled by an attacker allows interception of OAuth authorization codes, enabling token theft from users who authenticate against the application.
requiredDataConnectors:
  - connectorId: AzureActiveDirectory
    dataTypes:
      - AuditLogs
tactics:
  - Persistence
  - CredentialAccess
relevantTechniques:
  - T1528
query: |
  let timeframe = 1d;
  AuditLogs
  | where TimeGenerated >= ago(timeframe)
  | where OperationName =~ "Update application"
  | where Result =~ "success"
  | mv-expand ModProp = TargetResources[0].modifiedProperties
  | where tostring(ModProp.displayName) =~ "ReplyUrls"
  | extend OldReplyUrls = tostring(ModProp.oldValue)
  | extend NewReplyUrls = tostring(ModProp.newValue)
  | extend AppName = tostring(TargetResources[0].displayName)
  | extend AppId   = tostring(TargetResources[0].id)
  | extend ActorUpn = tostring(InitiatedBy.user.userPrincipalName)
  | extend ActorApp = tostring(InitiatedBy.app.displayName)
  | extend ActorIp  = iff(
        isnotempty(tostring(InitiatedBy.user.ipAddress)),
        tostring(InitiatedBy.user.ipAddress),
        tostring(InitiatedBy.app.ipAddress))
  | extend AccountName      = iff(ActorUpn has "@",
        tostring(split(ActorUpn, "@")[0]), "")
  | extend AccountUPNSuffix = iff(ActorUpn has "@",
        tostring(split(ActorUpn, "@")[1]), "")
  | project
      TimeGenerated,
      AppName,
      AppId,
      OldReplyUrls,
      NewReplyUrls,
      ActorUpn,
      ActorApp,
      AccountName,
      AccountUPNSuffix,
      ActorIp,
      CorrelationId
  | sort by TimeGenerated desc
entityMappings:
  - entityType: Account
    fieldMappings:
      - identifier: FullName
        columnName: ActorUpn
      - identifier: Name
        columnName: AccountName
      - identifier: UPNSuffix
        columnName: AccountUPNSuffix
  - entityType: IP
    fieldMappings:
      - identifier: Address
        columnName: ActorIp
version: 1.0.0
metadata:
    source:
        kind: Community
    author:
        name: descambiado
    support:
        tier: Community
    categories:
        domains: [ "Security - Threat Protection", "Identity" ]