PulseConnectSecure - Large Number of Distinct Failed User Logins

let threshold = 100;
PulseConnectSecure
| where Messages startswith "Login failed"
| summarize dcount(User) by Computer, bin(TimeGenerated, 15m)
| where dcount_User > threshold

query: |
  let threshold = 100;
  PulseConnectSecure
  | where Messages startswith "Login failed"
  | summarize dcount(User) by Computer, bin(TimeGenerated, 15m)
  | where dcount_User > threshold  
queryPeriod: 1h
queryFrequency: 1h
status: Available
id: 1fa1528e-f746-4794-8a41-14827f4cb798
entityMappings:
- entityType: Host
  fieldMappings:
  - columnName: Computer
    identifier: FullName
relevantTechniques:
- T1110
OriginalUri: https://github.com/Azure/Azure-Sentinel/blob/master/Solutions/Pulse Connect Secure/Analytic Rules/PulseConnectSecureVPN-DistinctFailedUserLogin.yaml
requiredDataConnectors:
- connectorId: SyslogAma
  datatypes:
  - Syslog
name: PulseConnectSecure - Large Number of Distinct Failed User Logins
description: |
    'This query identifies evidence of failed login attempts from a large number of distinct users on a Pulse Connect Secure VPN server'
tactics:
- CredentialAccess
severity: Medium
triggerThreshold: 0
version: 1.0.4
kind: Scheduled
triggerOperator: gt

{
  "$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/1fa1528e-f746-4794-8a41-14827f4cb798')]",
      "kind": "Scheduled",
      "name": "[concat(parameters('workspace'),'/Microsoft.SecurityInsights/1fa1528e-f746-4794-8a41-14827f4cb798')]",
      "properties": {
        "alertRuleTemplateName": "1fa1528e-f746-4794-8a41-14827f4cb798",
        "customDetails": null,
        "description": "'This query identifies evidence of failed login attempts from a large number of distinct users on a Pulse Connect Secure VPN server'\n",
        "displayName": "PulseConnectSecure - Large Number of Distinct Failed User Logins",
        "enabled": true,
        "entityMappings": [
          {
            "entityType": "Host",
            "fieldMappings": [
              {
                "columnName": "Computer",
                "identifier": "FullName"
              }
            ]
          }
        ],
        "OriginalUri": "https://github.com/Azure/Azure-Sentinel/blob/master/Solutions/Pulse Connect Secure/Analytic Rules/PulseConnectSecureVPN-DistinctFailedUserLogin.yaml",
        "query": "let threshold = 100;\nPulseConnectSecure\n| where Messages startswith \"Login failed\"\n| summarize dcount(User) by Computer, bin(TimeGenerated, 15m)\n| where dcount_User > threshold\n",
        "queryFrequency": "PT1H",
        "queryPeriod": "PT1H",
        "severity": "Medium",
        "status": "Available",
        "subTechniques": [],
        "suppressionDuration": "PT1H",
        "suppressionEnabled": false,
        "tactics": [
          "CredentialAccess"
        ],
        "techniques": [
          "T1110"
        ],
        "templateVersion": "1.0.4",
        "triggerOperator": "GreaterThan",
        "triggerThreshold": 0
      },
      "type": "Microsoft.OperationalInsights/workspaces/providers/alertRules"
    }
  ]
}