SUPERNOVA webshell

W3CIISLog
| where csMethod == 'GET'
| where isnotempty(csUriStem) and isnotempty(csUriQuery)
| where csUriStem contains "logoimagehandler.ashx"
| where csUriQuery contains "codes" and csUriQuery contains "clazz" and csUriQuery contains "method" and csUriQuery contains "args"
| extend timestamp = TimeGenerated, IPCustomEntity = cIP, HostCustomEntity = Computer, AccountCustomEntity = csUserName

severity: High
triggerThreshold: 0
metadata:
  source:
    kind: Community
  support:
    tier: Community
  categories:
    domains:
    - Security - Others
  author:
    name: Ajeet Prakash
queryFrequency: 1d
requiredDataConnectors:
- connectorId: AzureMonitor(IIS)
  dataTypes:
  - W3CIISLog
id: 2acc91c3-17c2-4388-938e-4eac2d5894e8
version: 1.0.3
name: SUPERNOVA webshell
kind: Scheduled
OriginalUri: https://github.com/Azure/Azure-Sentinel/blob/master/Detections/W3CIISLog/Supernovawebshell.yaml
queryPeriod: 1d
relevantTechniques:
- T1505
- T1071
triggerOperator: gt
tactics:
- Persistence
- CommandandControl
query: |
  W3CIISLog
  | where csMethod == 'GET'
  | where isnotempty(csUriStem) and isnotempty(csUriQuery)
  | where csUriStem contains "logoimagehandler.ashx"
  | where csUriQuery contains "codes" and csUriQuery contains "clazz" and csUriQuery contains "method" and csUriQuery contains "args"
  | extend timestamp = TimeGenerated, IPCustomEntity = cIP, HostCustomEntity = Computer, AccountCustomEntity = csUserName  
entityMappings:
- entityType: Account
  fieldMappings:
  - identifier: FullName
    columnName: AccountCustomEntity
- entityType: Host
  fieldMappings:
  - identifier: FullName
    columnName: HostCustomEntity
- entityType: IP
  fieldMappings:
  - identifier: Address
    columnName: IPCustomEntity
description: |
  'Identifies SUPERNOVA webshell based on W3CIISLog data.
   References:
   - https://unit42.paloaltonetworks.com/solarstorm-supernova/'  

{
  "$schema": "https://schema.management.azure.com/schemas/2019-04-01/deploymentTemplate.json#",
  "contentVersion": "1.0.0.0",
  "parameters": {
    "workspace": {
      "type": "String"
    }
  },
  "resources": [
    {
      "id": "[concat(resourceId('Microsoft.OperationalInsights/workspaces/providers', parameters('workspace'), 'Microsoft.SecurityInsights'),'/alertRules/2acc91c3-17c2-4388-938e-4eac2d5894e8')]",
      "name": "[concat(parameters('workspace'),'/Microsoft.SecurityInsights/2acc91c3-17c2-4388-938e-4eac2d5894e8')]",
      "type": "Microsoft.OperationalInsights/workspaces/providers/alertRules",
      "kind": "Scheduled",
      "apiVersion": "2022-11-01",
      "properties": {
        "displayName": "SUPERNOVA webshell",
        "description": "'Identifies SUPERNOVA webshell based on W3CIISLog data.\n References:\n - https://unit42.paloaltonetworks.com/solarstorm-supernova/'\n",
        "severity": "High",
        "enabled": true,
        "query": "W3CIISLog\n| where csMethod == 'GET'\n| where isnotempty(csUriStem) and isnotempty(csUriQuery)\n| where csUriStem contains \"logoimagehandler.ashx\"\n| where csUriQuery contains \"codes\" and csUriQuery contains \"clazz\" and csUriQuery contains \"method\" and csUriQuery contains \"args\"\n| extend timestamp = TimeGenerated, IPCustomEntity = cIP, HostCustomEntity = Computer, AccountCustomEntity = csUserName\n",
        "queryFrequency": "P1D",
        "queryPeriod": "P1D",
        "triggerOperator": "GreaterThan",
        "triggerThreshold": 0,
        "suppressionDuration": "PT1H",
        "suppressionEnabled": false,
        "tactics": [
          "Persistence",
          "CommandandControl"
        ],
        "techniques": [
          "T1505",
          "T1071"
        ],
        "alertRuleTemplateName": "2acc91c3-17c2-4388-938e-4eac2d5894e8",
        "customDetails": null,
        "entityMappings": [
          {
            "fieldMappings": [
              {
                "columnName": "AccountCustomEntity",
                "identifier": "FullName"
              }
            ],
            "entityType": "Account"
          },
          {
            "fieldMappings": [
              {
                "columnName": "HostCustomEntity",
                "identifier": "FullName"
              }
            ],
            "entityType": "Host"
          },
          {
            "fieldMappings": [
              {
                "columnName": "IPCustomEntity",
                "identifier": "Address"
              }
            ],
            "entityType": "IP"
          }
        ],
        "OriginalUri": "https://github.com/Azure/Azure-Sentinel/blob/master/Detections/W3CIISLog/Supernovawebshell.yaml",
        "templateVersion": "1.0.3"
      }
    }
  ]
}