Match Legitimate Name or Location - 2

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Id	dd22dc4f-ab7c-4d0a-84ad-cc393638ba31
Rulename	Match Legitimate Name or Location - 2
Description	Attackers often match or approximate the name or location of legitimate files to avoid detection rules that are based trust of on certain operating system processes. This query detects mismatches in the parent-child relationship of core operating system processes to uncover different masquerading attempts.
Severity	Medium
Tactics	DefenseEvasion
Techniques	T1036.005
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/MatchLegitimateNameOrLocation.yaml
Version	1.0.1
Arm template	dd22dc4f-ab7c-4d0a-84ad-cc393638ba31.json

KQL

let ProcessRelations=datatable(ImageFile:string,ExpectedParent:dynamic) [
  "smss.exe", dynamic(["smss.exe", "ntoskrnl.exe", ""]),
  "crmss.exe", dynamic(["smss.exe"]),
  "wininit.exe", dynamic(["smss.exe"]),
  "winlogon.exe", dynamic(["smss.exe"]),
  "services.exe", dynamic(["wininit.exe"]),
  "lsaiso.exe", dynamic(["wininit.exe"]),
  "lsass.exe", dynamic(["wininit.exe"]),
  "spoolsv.exe", dynamic(["services.exe"]),
  "dllhost.exe", dynamic(["svchost.exe", "services.exe"]),
  "lsm.exe", dynamic(["wininit.exe"]),
  "svchost.exe", dynamic(["services.exe", "msmpeng.exe"]),
  "runtimebroker.exe", dynamic(["svchost.exe"]),
  "taskhostw.exe", dynamic(["svchost.exe"]),
  "userinit.exe", dynamic(["winlogon.exe"])
  // Explorer can have a lot of parents in some environments
  //,"explorer.exe", dynamic(["userinit.exe"])
];
DeviceProcessEvents
| extend ImageFile = tostring(tolower(parse_path(tostring(FolderPath)).Filename))
| extend ParentFile = tostring(tolower(parse_path(tostring(InitiatingProcessFolderPath)).Filename))
| lookup kind=inner ProcessRelations on ImageFile
| where not(set_has_element(ExpectedParent,ParentFile))

YAML

OriginalUri: https://github.com/Azure/Azure-Sentinel/blob/master/Solutions/FalconFriday/Analytic Rules/MatchLegitimateNameOrLocation.yaml
query: |
  let ProcessRelations=datatable(ImageFile:string,ExpectedParent:dynamic) [
    "smss.exe", dynamic(["smss.exe", "ntoskrnl.exe", ""]),
    "crmss.exe", dynamic(["smss.exe"]),
    "wininit.exe", dynamic(["smss.exe"]),
    "winlogon.exe", dynamic(["smss.exe"]),
    "services.exe", dynamic(["wininit.exe"]),
    "lsaiso.exe", dynamic(["wininit.exe"]),
    "lsass.exe", dynamic(["wininit.exe"]),
    "spoolsv.exe", dynamic(["services.exe"]),
    "dllhost.exe", dynamic(["svchost.exe", "services.exe"]),
    "lsm.exe", dynamic(["wininit.exe"]),
    "svchost.exe", dynamic(["services.exe", "msmpeng.exe"]),
    "runtimebroker.exe", dynamic(["svchost.exe"]),
    "taskhostw.exe", dynamic(["svchost.exe"]),
    "userinit.exe", dynamic(["winlogon.exe"])
    // Explorer can have a lot of parents in some environments
    //,"explorer.exe", dynamic(["userinit.exe"])
  ];
  DeviceProcessEvents
  | extend ImageFile = tostring(tolower(parse_path(tostring(FolderPath)).Filename))
  | extend ParentFile = tostring(tolower(parse_path(tostring(InitiatingProcessFolderPath)).Filename))
  | lookup kind=inner ProcessRelations on ImageFile
  | where not(set_has_element(ExpectedParent,ParentFile))  
description: |
  Attackers often match or approximate the name or location of legitimate files to avoid detection rules that are based trust of on certain operating system processes.
  This query detects mismatches in the parent-child relationship of core operating system processes to uncover different masquerading attempts.  
severity: Medium
requiredDataConnectors:
- dataTypes:
  - DeviceProcessEvents
  connectorId: MicrosoftThreatProtection
name: Match Legitimate Name or Location - 2
triggerThreshold: 0
tactics:
- DefenseEvasion
version: 1.0.1
relevantTechniques:
- T1036.005
triggerOperator: gt
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
id: dd22dc4f-ab7c-4d0a-84ad-cc393638ba31
status: Available
kind: Scheduled
queryFrequency: 1h
queryPeriod: 1h

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/dd22dc4f-ab7c-4d0a-84ad-cc393638ba31')]",
      "kind": "Scheduled",
      "name": "[concat(parameters('workspace'),'/Microsoft.SecurityInsights/dd22dc4f-ab7c-4d0a-84ad-cc393638ba31')]",
      "properties": {
        "alertRuleTemplateName": "dd22dc4f-ab7c-4d0a-84ad-cc393638ba31",
        "customDetails": null,
        "description": "Attackers often match or approximate the name or location of legitimate files to avoid detection rules that are based trust of on certain operating system processes.\nThis query detects mismatches in the parent-child relationship of core operating system processes to uncover different masquerading attempts.\n",
        "displayName": "Match Legitimate Name or Location - 2",
        "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/MatchLegitimateNameOrLocation.yaml",
        "query": "let ProcessRelations=datatable(ImageFile:string,ExpectedParent:dynamic) [\n  \"smss.exe\", dynamic([\"smss.exe\", \"ntoskrnl.exe\", \"\"]),\n  \"crmss.exe\", dynamic([\"smss.exe\"]),\n  \"wininit.exe\", dynamic([\"smss.exe\"]),\n  \"winlogon.exe\", dynamic([\"smss.exe\"]),\n  \"services.exe\", dynamic([\"wininit.exe\"]),\n  \"lsaiso.exe\", dynamic([\"wininit.exe\"]),\n  \"lsass.exe\", dynamic([\"wininit.exe\"]),\n  \"spoolsv.exe\", dynamic([\"services.exe\"]),\n  \"dllhost.exe\", dynamic([\"svchost.exe\", \"services.exe\"]),\n  \"lsm.exe\", dynamic([\"wininit.exe\"]),\n  \"svchost.exe\", dynamic([\"services.exe\", \"msmpeng.exe\"]),\n  \"runtimebroker.exe\", dynamic([\"svchost.exe\"]),\n  \"taskhostw.exe\", dynamic([\"svchost.exe\"]),\n  \"userinit.exe\", dynamic([\"winlogon.exe\"])\n  // Explorer can have a lot of parents in some environments\n  //,\"explorer.exe\", dynamic([\"userinit.exe\"])\n];\nDeviceProcessEvents\n| extend ImageFile = tostring(tolower(parse_path(tostring(FolderPath)).Filename))\n| extend ParentFile = tostring(tolower(parse_path(tostring(InitiatingProcessFolderPath)).Filename))\n| lookup kind=inner ProcessRelations on ImageFile\n| where not(set_has_element(ExpectedParent,ParentFile))\n",
        "queryFrequency": "PT1H",
        "queryPeriod": "PT1H",
        "severity": "Medium",
        "status": "Available",
        "subTechniques": [
          "T1036.005"
        ],
        "suppressionDuration": "PT1H",
        "suppressionEnabled": false,
        "tactics": [
          "DefenseEvasion"
        ],
        "techniques": [
          "T1036"
        ],
        "templateVersion": "1.0.1",
        "triggerOperator": "GreaterThan",
        "triggerThreshold": 0
      },
      "type": "Microsoft.OperationalInsights/workspaces/providers/alertRules"
    }
  ]
}