Remote Desktop Protocol - SharpRDP

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Id	cc46e76c-0d04-40b0-9c8b-929aa40513e7
Rulename	Remote Desktop Protocol - SharpRDP
Description	This detection monitors for the behavior that SharpRDP exhibits on the target system. The most relevant is leveraging taskmgr.exe to gain elevated execution, which means that taskmgr.exe is creating unexpected child processes.
Severity	Medium
Tactics	LateralMovement
Techniques	T1021.001
Required data connectors	MicrosoftThreatProtection
Kind	Scheduled
Query frequency	1h
Query period	1h
Trigger threshold	0
Trigger operator	gt
Source Uri	https://github.com/Azure/Azure-Sentinel/blob/master/Solutions/FalconFriday/Analytic Rules/RemoteDesktopProtocol.yaml
Version	1.0.0
Arm template	cc46e76c-0d04-40b0-9c8b-929aa40513e7.json

KQL

let executions = DeviceProcessEvents
| where InitiatingProcessFileName contains "taskmgr" and AccountName !contains "_ladm" // Include your LAPS /RID500 admin naming convention here. 
// Add the below filter to look for stock SharpRDP behavior. However, with minorchanges to the stock version of SharpRDP the filter below can be bypassed.
//| where not(InitiatingProcessCommandLine has_any ("/1","/2","/3","/4"))
| where not(FolderPath =~ @"c:\Windows\system32\WerFault.exe" and ProcessCommandLine contains "-u -p")
| where not(FolderPath =~ @"c:\windows\system32\mmc.exe" and ProcessCommandLine contains @"C:\WINDOWS\System32\services.msc")
| where not(FolderPath =~ @"c:\windows\system32\resmon.exe");
executions
| join kind=leftsemi  (DeviceLogonEvents
| where LogonType in ('Unlock', 'RemoteInteractive') and not (LogonType == 'Unlock' and RemoteIP == '127.0.0.1') and RemoteIP != "" and ActionType == "LogonSuccess") on DeviceId, LogonId

YAML

status: Available
triggerOperator: gt
triggerThreshold: 0
name: Remote Desktop Protocol - SharpRDP
OriginalUri: https://github.com/Azure/Azure-Sentinel/blob/master/Solutions/FalconFriday/Analytic Rules/RemoteDesktopProtocol.yaml
queryPeriod: 1h
severity: Medium
kind: Scheduled
entityMappings:
- entityType: Host
  fieldMappings:
  - columnName: DeviceName
    identifier: FullName
- entityType: Account
  fieldMappings:
  - columnName: AccountSid
    identifier: Sid
  - columnName: AccountName
    identifier: Name
  - columnName: AccountDomain
    identifier: NTDomain
- entityType: Process
  fieldMappings:
  - columnName: ProcessCommandLine
    identifier: CommandLine
queryFrequency: 1h
relevantTechniques:
- T1021.001
requiredDataConnectors:
- dataTypes:
  - DeviceProcessEvents
  - DeviceLogonEvents
  connectorId: MicrosoftThreatProtection
description: |
    This detection monitors for the behavior that SharpRDP exhibits on the target system. The most relevant is leveraging taskmgr.exe to gain elevated execution, which means that taskmgr.exe is creating unexpected child processes.
tactics:
- LateralMovement
query: |
  let executions = DeviceProcessEvents
  | where InitiatingProcessFileName contains "taskmgr" and AccountName !contains "_ladm" // Include your LAPS /RID500 admin naming convention here. 
  // Add the below filter to look for stock SharpRDP behavior. However, with minorchanges to the stock version of SharpRDP the filter below can be bypassed.
  //| where not(InitiatingProcessCommandLine has_any ("/1","/2","/3","/4"))
  | where not(FolderPath =~ @"c:\Windows\system32\WerFault.exe" and ProcessCommandLine contains "-u -p")
  | where not(FolderPath =~ @"c:\windows\system32\mmc.exe" and ProcessCommandLine contains @"C:\WINDOWS\System32\services.msc")
  | where not(FolderPath =~ @"c:\windows\system32\resmon.exe");
  executions
  | join kind=leftsemi  (DeviceLogonEvents
  | where LogonType in ('Unlock', 'RemoteInteractive') and not (LogonType == 'Unlock' and RemoteIP == '127.0.0.1') and RemoteIP != "" and ActionType == "LogonSuccess") on DeviceId, LogonId  
id: cc46e76c-0d04-40b0-9c8b-929aa40513e7
version: 1.0.0

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/cc46e76c-0d04-40b0-9c8b-929aa40513e7')]",
      "kind": "Scheduled",
      "name": "[concat(parameters('workspace'),'/Microsoft.SecurityInsights/cc46e76c-0d04-40b0-9c8b-929aa40513e7')]",
      "properties": {
        "alertRuleTemplateName": "cc46e76c-0d04-40b0-9c8b-929aa40513e7",
        "customDetails": null,
        "description": "This detection monitors for the behavior that SharpRDP exhibits on the target system. The most relevant is leveraging taskmgr.exe to gain elevated execution, which means that taskmgr.exe is creating unexpected child processes.\n",
        "displayName": "Remote Desktop Protocol - SharpRDP",
        "enabled": true,
        "entityMappings": [
          {
            "entityType": "Host",
            "fieldMappings": [
              {
                "columnName": "DeviceName",
                "identifier": "FullName"
              }
            ]
          },
          {
            "entityType": "Account",
            "fieldMappings": [
              {
                "columnName": "AccountSid",
                "identifier": "Sid"
              },
              {
                "columnName": "AccountName",
                "identifier": "Name"
              },
              {
                "columnName": "AccountDomain",
                "identifier": "NTDomain"
              }
            ]
          },
          {
            "entityType": "Process",
            "fieldMappings": [
              {
                "columnName": "ProcessCommandLine",
                "identifier": "CommandLine"
              }
            ]
          }
        ],
        "OriginalUri": "https://github.com/Azure/Azure-Sentinel/blob/master/Solutions/FalconFriday/Analytic Rules/RemoteDesktopProtocol.yaml",
        "query": "let executions = DeviceProcessEvents\n| where InitiatingProcessFileName contains \"taskmgr\" and AccountName !contains \"_ladm\" // Include your LAPS /RID500 admin naming convention here. \n// Add the below filter to look for stock SharpRDP behavior. However, with minorchanges to the stock version of SharpRDP the filter below can be bypassed.\n//| where not(InitiatingProcessCommandLine has_any (\"/1\",\"/2\",\"/3\",\"/4\"))\n| where not(FolderPath =~ @\"c:\\Windows\\system32\\WerFault.exe\" and ProcessCommandLine contains \"-u -p\")\n| where not(FolderPath =~ @\"c:\\windows\\system32\\mmc.exe\" and ProcessCommandLine contains @\"C:\\WINDOWS\\System32\\services.msc\")\n| where not(FolderPath =~ @\"c:\\windows\\system32\\resmon.exe\");\nexecutions\n| join kind=leftsemi  (DeviceLogonEvents\n| where LogonType in ('Unlock', 'RemoteInteractive') and not (LogonType == 'Unlock' and RemoteIP == '127.0.0.1') and RemoteIP != \"\" and ActionType == \"LogonSuccess\") on DeviceId, LogonId\n",
        "queryFrequency": "PT1H",
        "queryPeriod": "PT1H",
        "severity": "Medium",
        "status": "Available",
        "subTechniques": [
          "T1021.001"
        ],
        "suppressionDuration": "PT1H",
        "suppressionEnabled": false,
        "tactics": [
          "LateralMovement"
        ],
        "techniques": [
          "T1021"
        ],
        "templateVersion": "1.0.0",
        "triggerOperator": "GreaterThan",
        "triggerThreshold": 0
      },
      "type": "Microsoft.OperationalInsights/workspaces/providers/alertRules"
    }
  ]
}