Anomaly Sign In Event from an IP

let LookBack = 1h;
let Data = (
SigninLogs
| where TimeGenerated >= ago(LookBack)
| where parse_json(NetworkLocationDetails)[0].networkType != "trustedNamedLocation" // Excludes known tagged networks
// Counts the number of sign in events in the last hour every 15 minutes by IP
| make-series EventCounts = count() on TimeGenerated from ago(LookBack) to now() step 15m by IPAddress 
);
let AnomalyAlert = (
Data
| extend (Anomalies, Score, Baseline) = series_decompose_anomalies(EventCounts,1.5,-1,'linefit')
| mv-expand EventCounts,TimeGenerated,Anomalies to typeof(double),Baseline to typeof(long),Score to typeof(double)
| where Anomalies > 0
);
AnomalyAlert
| join kind = inner (SigninLogs
| where TimeGenerated between (ago(LookBack) .. now())
| where parse_json(NetworkLocationDetails)[0].networkType != "trustedNamedLocation"
| extend PasswordResult = tostring(parse_json(AuthenticationDetails).authenticationStepResultDetail)
| summarize UserCount = dcount(UserPrincipalName), UserList = make_set(UserPrincipalName), AppName = make_set(AppDisplayName), PasswordResult = make_list(PasswordResult) by IPAddress) on IPAddress
| where PasswordResult has "Correct Password"
| where UserCount > 1 // looks for events targeting more than one user.

relevantTechniques:
- T1078
OriginalUri: https://github.com/Azure/Azure-Sentinel/blob/master/Detections/Anomalies/SignInAnomaly.yaml
kind: Scheduled
triggerOperator: gt
requiredDataConnectors:
- dataTypes:
  - SigninLogs
  connectorId: AzureActiveDirectory
severity: Medium
entityMappings:
- fieldMappings:
  - identifier: Address
    columnName: IPAddress
  entityType: IP
version: 1.0.1
tactics:
- InitialAccess
triggerThreshold: 0
metadata:
  categories:
    domains:
    - Identity
  support:
    tier: Community
  source:
    kind: Community
  author:
    name: Juanse
queryPeriod: 1h
queryFrequency: 1h
id: 9c1e9381-79dd-4ddf-9570-b73a1dc59fe0
name: Anomaly Sign In Event from an IP
description: |
    'Identifies sign-in anomalies from an IP in the last hour, targeting multiple users where the password is correct after multiple attempts'
query: |
  let LookBack = 1h;
  let Data = (
  SigninLogs
  | where TimeGenerated >= ago(LookBack)
  | where parse_json(NetworkLocationDetails)[0].networkType != "trustedNamedLocation" // Excludes known tagged networks
  // Counts the number of sign in events in the last hour every 15 minutes by IP
  | make-series EventCounts = count() on TimeGenerated from ago(LookBack) to now() step 15m by IPAddress 
  );
  let AnomalyAlert = (
  Data
  | extend (Anomalies, Score, Baseline) = series_decompose_anomalies(EventCounts,1.5,-1,'linefit')
  | mv-expand EventCounts,TimeGenerated,Anomalies to typeof(double),Baseline to typeof(long),Score to typeof(double)
  | where Anomalies > 0
  );
  AnomalyAlert
  | join kind = inner (SigninLogs
  | where TimeGenerated between (ago(LookBack) .. now())
  | where parse_json(NetworkLocationDetails)[0].networkType != "trustedNamedLocation"
  | extend PasswordResult = tostring(parse_json(AuthenticationDetails).authenticationStepResultDetail)
  | summarize UserCount = dcount(UserPrincipalName), UserList = make_set(UserPrincipalName), AppName = make_set(AppDisplayName), PasswordResult = make_list(PasswordResult) by IPAddress) on IPAddress
  | where PasswordResult has "Correct Password"
  | where UserCount > 1 // looks for events targeting more than one user.  
customDetails:
  UserList: UserList
  AppName: AppName
  UserCount: UserCount
  Baseline: Baseline
  PasswordResult: PasswordResult
  Score: Score

{
  "$schema": "https://schema.management.azure.com/schemas/2019-04-01/deploymentTemplate.json#",
  "contentVersion": "1.0.0.0",
  "parameters": {
    "workspace": {
      "type": "String"
    }
  },
  "resources": [
    {
      "apiVersion": "2024-01-01-preview",
      "id": "[concat(resourceId('Microsoft.OperationalInsights/workspaces/providers', parameters('workspace'), 'Microsoft.SecurityInsights'),'/alertRules/9c1e9381-79dd-4ddf-9570-b73a1dc59fe0')]",
      "kind": "Scheduled",
      "name": "[concat(parameters('workspace'),'/Microsoft.SecurityInsights/9c1e9381-79dd-4ddf-9570-b73a1dc59fe0')]",
      "properties": {
        "alertRuleTemplateName": "9c1e9381-79dd-4ddf-9570-b73a1dc59fe0",
        "customDetails": {
          "AppName": "AppName",
          "Baseline": "Baseline",
          "PasswordResult": "PasswordResult",
          "Score": "Score",
          "UserCount": "UserCount",
          "UserList": "UserList"
        },
        "description": "'Identifies sign-in anomalies from an IP in the last hour, targeting multiple users where the password is correct after multiple attempts'\n",
        "displayName": "Anomaly Sign In Event from an IP",
        "enabled": true,
        "entityMappings": [
          {
            "entityType": "IP",
            "fieldMappings": [
              {
                "columnName": "IPAddress",
                "identifier": "Address"
              }
            ]
          }
        ],
        "OriginalUri": "https://github.com/Azure/Azure-Sentinel/blob/master/Detections/Anomalies/SignInAnomaly.yaml",
        "query": "let LookBack = 1h;\nlet Data = (\nSigninLogs\n| where TimeGenerated >= ago(LookBack)\n| where parse_json(NetworkLocationDetails)[0].networkType != \"trustedNamedLocation\" // Excludes known tagged networks\n// Counts the number of sign in events in the last hour every 15 minutes by IP\n| make-series EventCounts = count() on TimeGenerated from ago(LookBack) to now() step 15m by IPAddress \n);\nlet AnomalyAlert = (\nData\n| extend (Anomalies, Score, Baseline) = series_decompose_anomalies(EventCounts,1.5,-1,'linefit')\n| mv-expand EventCounts,TimeGenerated,Anomalies to typeof(double),Baseline to typeof(long),Score to typeof(double)\n| where Anomalies > 0\n);\nAnomalyAlert\n| join kind = inner (SigninLogs\n| where TimeGenerated between (ago(LookBack) .. now())\n| where parse_json(NetworkLocationDetails)[0].networkType != \"trustedNamedLocation\"\n| extend PasswordResult = tostring(parse_json(AuthenticationDetails).authenticationStepResultDetail)\n| summarize UserCount = dcount(UserPrincipalName), UserList = make_set(UserPrincipalName), AppName = make_set(AppDisplayName), PasswordResult = make_list(PasswordResult) by IPAddress) on IPAddress\n| where PasswordResult has \"Correct Password\"\n| where UserCount > 1 // looks for events targeting more than one user.\n",
        "queryFrequency": "PT1H",
        "queryPeriod": "PT1H",
        "severity": "Medium",
        "subTechniques": [],
        "suppressionDuration": "PT1H",
        "suppressionEnabled": false,
        "tactics": [
          "InitialAccess"
        ],
        "techniques": [
          "T1078"
        ],
        "templateVersion": "1.0.1",
        "triggerOperator": "GreaterThan",
        "triggerThreshold": 0
      },
      "type": "Microsoft.OperationalInsights/workspaces/providers/alertRules"
    }
  ]
}