App Gateway WAF - Scanner Detection

Back


Id	9b8dd8fd-f192-42eb-84f6-541920400a7a
Rulename	App Gateway WAF - Scanner Detection
Description	Identifies a match for a Scanner detection user agent based attack in the App Gateway WAF logs. The threshold value in the query can be changed as per your infrastructure’s requirements. References: https://owasp.org/www-community/Vulnerability_Scanning_Tools
Severity	High
Tactics	DefenseEvasion Execution InitialAccess Reconnaissance Discovery
Techniques	T1548 T1203 T1190 T1595 T1046
Required data connectors	WAF
Kind	Scheduled
Query frequency	6h
Query period	6h
Trigger threshold	0
Trigger operator	gt
Source Uri	https://github.com/Azure/Azure-Sentinel/blob/master/Solutions/Azure Web Application Firewall (WAF)/Analytic Rules/App-GW-WAF-Scanner-detection.yaml
Version	1.0.2
Arm template	9b8dd8fd-f192-42eb-84f6-541920400a7a.json

KQL

let Threshold = 3;
AzureDiagnostics
| where ResourceProvider == 'MICROSOFT.NETWORK' and Category == 'ApplicationGatewayFirewallLog'
| where action_s == "Matched"
| where Message contains "Found User-Agent associated with security scanner"
| project transactionId_g, hostname_s, requestUri_s, TimeGenerated, clientIp_s, Message, details_message_s, details_data_s
| join kind = inner(
AzureDiagnostics
| where ResourceProvider == 'MICROSOFT.NETWORK' and Category == 'ApplicationGatewayFirewallLog'
| where action_s == "Blocked"
) on transactionId_g
| extend Uri = strcat(hostname_s,requestUri_s)
| summarize StartTime = min(TimeGenerated), EndTime = max(TimeGenerated), TransactionID = make_set(transactionId_g), Message = make_set(Message), Detail_Message = make_set(details_message_s), Detail_Data = make_set(details_data_s), Total_TransactionId = dcount(transactionId_g) by clientIp_s, Uri, action_s
| where Total_TransactionId >= Threshold

YAML

relevantTechniques:
- T1548
- T1203
- T1190
- T1595
- T1046
name: App Gateway WAF - Scanner Detection
requiredDataConnectors:
- dataTypes:
  - AzureDiagnostics
  connectorId: WAF
entityMappings:
- fieldMappings:
  - identifier: Url
    columnName: Uri
  entityType: URL
- fieldMappings:
  - identifier: Address
    columnName: clientIp_s
  entityType: IP
triggerThreshold: 0
id: 9b8dd8fd-f192-42eb-84f6-541920400a7a
tactics:
- DefenseEvasion
- Execution
- InitialAccess
- Reconnaissance
- Discovery
version: 1.0.2
OriginalUri: https://github.com/Azure/Azure-Sentinel/blob/master/Solutions/Azure Web Application Firewall (WAF)/Analytic Rules/App-GW-WAF-Scanner-detection.yaml
queryPeriod: 6h
kind: Scheduled
tags:
- Scanner Detection
queryFrequency: 6h
severity: High
status: Available
description: |
  'Identifies a match for a Scanner detection user agent based attack in the App Gateway WAF logs. The threshold value in the query can be changed as per your infrastructure's requirements.
  References: https://owasp.org/www-community/Vulnerability_Scanning_Tools'  
query: |
  let Threshold = 3;
  AzureDiagnostics
  | where ResourceProvider == 'MICROSOFT.NETWORK' and Category == 'ApplicationGatewayFirewallLog'
  | where action_s == "Matched"
  | where Message contains "Found User-Agent associated with security scanner"
  | project transactionId_g, hostname_s, requestUri_s, TimeGenerated, clientIp_s, Message, details_message_s, details_data_s
  | join kind = inner(
  AzureDiagnostics
  | where ResourceProvider == 'MICROSOFT.NETWORK' and Category == 'ApplicationGatewayFirewallLog'
  | where action_s == "Blocked"
  ) on transactionId_g
  | extend Uri = strcat(hostname_s,requestUri_s)
  | summarize StartTime = min(TimeGenerated), EndTime = max(TimeGenerated), TransactionID = make_set(transactionId_g), Message = make_set(Message), Detail_Message = make_set(details_message_s), Detail_Data = make_set(details_data_s), Total_TransactionId = dcount(transactionId_g) by clientIp_s, Uri, action_s
  | where Total_TransactionId >= Threshold  
triggerOperator: gt

ARM

{
  "$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/9b8dd8fd-f192-42eb-84f6-541920400a7a')]",
      "kind": "Scheduled",
      "name": "[concat(parameters('workspace'),'/Microsoft.SecurityInsights/9b8dd8fd-f192-42eb-84f6-541920400a7a')]",
      "properties": {
        "alertRuleTemplateName": "9b8dd8fd-f192-42eb-84f6-541920400a7a",
        "customDetails": null,
        "description": "'Identifies a match for a Scanner detection user agent based attack in the App Gateway WAF logs. The threshold value in the query can be changed as per your infrastructure's requirements.\nReferences: https://owasp.org/www-community/Vulnerability_Scanning_Tools'\n",
        "displayName": "App Gateway WAF - Scanner Detection",
        "enabled": true,
        "entityMappings": [
          {
            "entityType": "URL",
            "fieldMappings": [
              {
                "columnName": "Uri",
                "identifier": "Url"
              }
            ]
          },
          {
            "entityType": "IP",
            "fieldMappings": [
              {
                "columnName": "clientIp_s",
                "identifier": "Address"
              }
            ]
          }
        ],
        "OriginalUri": "https://github.com/Azure/Azure-Sentinel/blob/master/Solutions/Azure Web Application Firewall (WAF)/Analytic Rules/App-GW-WAF-Scanner-detection.yaml",
        "query": "let Threshold = 3;\nAzureDiagnostics\n| where ResourceProvider == 'MICROSOFT.NETWORK' and Category == 'ApplicationGatewayFirewallLog'\n| where action_s == \"Matched\"\n| where Message contains \"Found User-Agent associated with security scanner\"\n| project transactionId_g, hostname_s, requestUri_s, TimeGenerated, clientIp_s, Message, details_message_s, details_data_s\n| join kind = inner(\nAzureDiagnostics\n| where ResourceProvider == 'MICROSOFT.NETWORK' and Category == 'ApplicationGatewayFirewallLog'\n| where action_s == \"Blocked\"\n) on transactionId_g\n| extend Uri = strcat(hostname_s,requestUri_s)\n| summarize StartTime = min(TimeGenerated), EndTime = max(TimeGenerated), TransactionID = make_set(transactionId_g), Message = make_set(Message), Detail_Message = make_set(details_message_s), Detail_Data = make_set(details_data_s), Total_TransactionId = dcount(transactionId_g) by clientIp_s, Uri, action_s\n| where Total_TransactionId >= Threshold\n",
        "queryFrequency": "PT6H",
        "queryPeriod": "PT6H",
        "severity": "High",
        "status": "Available",
        "subTechniques": [],
        "suppressionDuration": "PT1H",
        "suppressionEnabled": false,
        "tactics": [
          "DefenseEvasion",
          "Discovery",
          "Execution",
          "InitialAccess",
          "Reconnaissance"
        ],
        "tags": [
          "Scanner Detection"
        ],
        "techniques": [
          "T1046",
          "T1190",
          "T1203",
          "T1548",
          "T1595"
        ],
        "templateVersion": "1.0.2",
        "triggerOperator": "GreaterThan",
        "triggerThreshold": 0
      },
      "type": "Microsoft.OperationalInsights/workspaces/providers/alertRules"
    }
  ]
}