Failed Logins from Unknown or Invalid User

// Adjust threshold for failed logins to reduce noise. This can be customized based on the organization's typical login patterns.
let FailureThreshold = 15;
// Adjust list of allowed users to reduce false positives. This can include service accounts, known test accounts, or any other accounts that are expected to generate failed login attempts.
let AllowedUsers = dynamic([]);
let FailedLogins = OktaSSO
| where eventType_s =~ "user.session.start" and outcome_reason_s =~ "VERIFICATION_ERROR"
| where isnotempty(actor_alternateId_s) and actor_alternateId_s !in (AllowedUsers)
| summarize count() by actor_alternateId_s, client_ipAddress_s, bin(TimeGenerated, 5m)
| where count_ > FailureThreshold
| project client_ipAddress_s, actor_alternateId_s;
OktaSSO
| join kind=inner (FailedLogins) on client_ipAddress_s, actor_alternateId_s
| where eventType_s =~ "user.session.start" and outcome_reason_s =~ "VERIFICATION_ERROR"
| summarize FailedLoginCount = count(), City = take_any(column_ifexists('client_geographicalContext_city_s', "")), Country = take_any(column_ifexists('client_geographicalContext_country_s', "")), LastSeen = max(column_ifexists('TimeGenerated', now())) by actor_alternateId_s, client_ipAddress_s
| sort by LastSeen desc
| extend AccountName = tostring(split(actor_alternateId_s, "@")[0]), AccountUPNSuffix = tostring(split(actor_alternateId_s, "@")[1])

severity: Medium
tactics:
- CredentialAccess
queryFrequency: 1h
id: 884be6e7-e568-418e-9c12-89229865ffde
query: |
  // Adjust threshold for failed logins to reduce noise. This can be customized based on the organization's typical login patterns.
  let FailureThreshold = 15;
  // Adjust list of allowed users to reduce false positives. This can include service accounts, known test accounts, or any other accounts that are expected to generate failed login attempts.
  let AllowedUsers = dynamic([]);
  let FailedLogins = OktaSSO
  | where eventType_s =~ "user.session.start" and outcome_reason_s =~ "VERIFICATION_ERROR"
  | where isnotempty(actor_alternateId_s) and actor_alternateId_s !in (AllowedUsers)
  | summarize count() by actor_alternateId_s, client_ipAddress_s, bin(TimeGenerated, 5m)
  | where count_ > FailureThreshold
  | project client_ipAddress_s, actor_alternateId_s;
  OktaSSO
  | join kind=inner (FailedLogins) on client_ipAddress_s, actor_alternateId_s
  | where eventType_s =~ "user.session.start" and outcome_reason_s =~ "VERIFICATION_ERROR"
  | summarize FailedLoginCount = count(), City = take_any(column_ifexists('client_geographicalContext_city_s', "")), Country = take_any(column_ifexists('client_geographicalContext_country_s', "")), LastSeen = max(column_ifexists('TimeGenerated', now())) by actor_alternateId_s, client_ipAddress_s
  | sort by LastSeen desc
  | extend AccountName = tostring(split(actor_alternateId_s, "@")[0]), AccountUPNSuffix = tostring(split(actor_alternateId_s, "@")[1])
entityMappings:
- fieldMappings:
  - identifier: Name
    columnName: AccountName
  - identifier: UPNSuffix
    columnName: AccountUPNSuffix
  entityType: Account
- fieldMappings:
  - identifier: Address
    columnName: client_ipAddress_s
  entityType: IP
customDetails:
  City: City
  Country: Country
  FailedLoginCount: FailedLoginCount
kind: Scheduled
triggerOperator: gt
name: Failed Logins from Unknown or Invalid User
version: 1.1.2
status: Available
requiredDataConnectors:
- dataTypes:
  - Okta_CL
  connectorId: OktaSSO
- dataTypes:
  - OktaSSO
  connectorId: OktaSSOv2
description: |
  This rule alerts when an unknown or invalid user generates more than 15 failed Okta management console login attempts from the same IP address within 5 minutes.
relevantTechniques:
- T1110.001
queryPeriod: 1h
OriginalUri: https://github.com/Azure/Azure-Sentinel/blob/master/Solutions/Okta%20Single%20Sign-On/Analytic%20Rules/FailedLoginsFromUnknownOrInvalidUser.yaml
triggerThreshold: 0
alertDetailsOverride:
  alertDisplayNameFormat: 'Failed logins from unknown or invalid user: {{actor_alternateId_s}} from IP {{client_ipAddress_s}}'
  alertDescriptionFormat: Account {{actor_alternateId_s}} generated {{FailedLoginCount}} failed logins from IP {{client_ipAddress_s}} in the last 5 minutes.

{
  "$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/884be6e7-e568-418e-9c12-89229865ffde')]",
      "kind": "Scheduled",
      "name": "[concat(parameters('workspace'),'/Microsoft.SecurityInsights/884be6e7-e568-418e-9c12-89229865ffde')]",
      "properties": {
        "alertDetailsOverride": {
          "alertDescriptionFormat": "Account {{actor_alternateId_s}} generated {{FailedLoginCount}} failed logins from IP {{client_ipAddress_s}} in the last 5 minutes.",
          "alertDisplayNameFormat": "Failed logins from unknown or invalid user: {{actor_alternateId_s}} from IP {{client_ipAddress_s}}"
        },
        "alertRuleTemplateName": "884be6e7-e568-418e-9c12-89229865ffde",
        "customDetails": {
          "City": "City",
          "Country": "Country",
          "FailedLoginCount": "FailedLoginCount"
        },
        "description": "This rule alerts when an unknown or invalid user generates more than 15 failed Okta management console login attempts from the same IP address within 5 minutes.\n",
        "displayName": "Failed Logins from Unknown or Invalid User",
        "enabled": true,
        "entityMappings": [
          {
            "entityType": "Account",
            "fieldMappings": [
              {
                "columnName": "AccountName",
                "identifier": "Name"
              },
              {
                "columnName": "AccountUPNSuffix",
                "identifier": "UPNSuffix"
              }
            ]
          },
          {
            "entityType": "IP",
            "fieldMappings": [
              {
                "columnName": "client_ipAddress_s",
                "identifier": "Address"
              }
            ]
          }
        ],
        "OriginalUri": "https://github.com/Azure/Azure-Sentinel/blob/master/Solutions/Okta%20Single%20Sign-On/Analytic%20Rules/FailedLoginsFromUnknownOrInvalidUser.yaml",
        "query": "// Adjust threshold for failed logins to reduce noise. This can be customized based on the organization's typical login patterns.\nlet FailureThreshold = 15;\n// Adjust list of allowed users to reduce false positives. This can include service accounts, known test accounts, or any other accounts that are expected to generate failed login attempts.\nlet AllowedUsers = dynamic([]);\nlet FailedLogins = OktaSSO\n| where eventType_s =~ \"user.session.start\" and outcome_reason_s =~ \"VERIFICATION_ERROR\"\n| where isnotempty(actor_alternateId_s) and actor_alternateId_s !in (AllowedUsers)\n| summarize count() by actor_alternateId_s, client_ipAddress_s, bin(TimeGenerated, 5m)\n| where count_ > FailureThreshold\n| project client_ipAddress_s, actor_alternateId_s;\nOktaSSO\n| join kind=inner (FailedLogins) on client_ipAddress_s, actor_alternateId_s\n| where eventType_s =~ \"user.session.start\" and outcome_reason_s =~ \"VERIFICATION_ERROR\"\n| summarize FailedLoginCount = count(), City = take_any(column_ifexists('client_geographicalContext_city_s', \"\")), Country = take_any(column_ifexists('client_geographicalContext_country_s', \"\")), LastSeen = max(column_ifexists('TimeGenerated', now())) by actor_alternateId_s, client_ipAddress_s\n| sort by LastSeen desc\n| extend AccountName = tostring(split(actor_alternateId_s, \"@\")[0]), AccountUPNSuffix = tostring(split(actor_alternateId_s, \"@\")[1])\n",
        "queryFrequency": "PT1H",
        "queryPeriod": "PT1H",
        "severity": "Medium",
        "status": "Available",
        "subTechniques": [
          "T1110.001"
        ],
        "suppressionDuration": "PT1H",
        "suppressionEnabled": false,
        "tactics": [
          "CredentialAccess"
        ],
        "techniques": [
          "T1110"
        ],
        "templateVersion": "1.1.2",
        "triggerOperator": "GreaterThan",
        "triggerThreshold": 0
      },
      "type": "Microsoft.OperationalInsights/workspaces/providers/alertRules"
    }
  ]
}