Potential Fodhelper UAC Bypass
Id | 56f3f35c-3aca-4437-a1fb-b7a84dc4af00 |
Rulename | Potential Fodhelper UAC Bypass |
Description | This detection looks for the steps required to conduct a UAC bypass using Fodhelper.exe. By default this detection looks for the setting of the required registry keys and the invoking of the process within 1 hour - this can be tweaked as required. |
Severity | Medium |
Tactics | PrivilegeEscalation |
Techniques | T1548.002 |
Required data connectors | SecurityEvents WindowsSecurityEvents |
Kind | Scheduled |
Query frequency | 2h |
Query period | 2h |
Trigger threshold | 0 |
Trigger operator | gt |
Source Uri | https://github.com/Azure/Azure-Sentinel/blob/master/Solutions/Windows Security Events/Analytic Rules/PotentialFodhelperUACBypass.yaml |
Version | 1.0.2 |
Arm template | 56f3f35c-3aca-4437-a1fb-b7a84dc4af00.json |
SecurityEvent
| where EventID == 4657
| parse ObjectName with "\\REGISTRY\\" KeyPrefix "\\" RegistryKey
| project-reorder RegistryKey
| where RegistryKey has "Software\\Classes\\ms-settings\\shell\\open\\command"
| extend TimeKey = bin(TimeGenerated, 1h)
| join (
SecurityEvent
| where EventID == 4688
| where Process =~ "fodhelper.exe"
| where ParentProcessName endswith "cmd.exe" or ParentProcessName endswith "powershell.exe" or ParentProcessName endswith "powershell_ise.exe"
| extend TimeKey = bin(TimeGenerated, 1h)) on TimeKey, Computer
| extend HostName = tostring(split(Computer, ".")[0]), DomainIndex = toint(indexof(Computer, '.'))
| extend HostNameDomain = iff(DomainIndex != -1, substring(Computer, DomainIndex + 1), Computer)
| extend AccountName = tostring(split(TargetAccount, @'\')[1]), AccountNTDomain = tostring(split(TargetAccount, @'\')[0])
entityMappings:
- entityType: Host
fieldMappings:
- identifier: FullName
columnName: Computer
- identifier: HostName
columnName: HostName
- identifier: DnsDomain
columnName: HostNameDomain
- entityType: Account
fieldMappings:
- identifier: FullName
columnName: TargetAccount
- identifier: Name
columnName: AccountName
- identifier: NTDomain
columnName: AccountNTDomain
queryFrequency: 2h
name: Potential Fodhelper UAC Bypass
severity: Medium
kind: Scheduled
tactics:
- PrivilegeEscalation
triggerThreshold: 0
query: |
SecurityEvent
| where EventID == 4657
| parse ObjectName with "\\REGISTRY\\" KeyPrefix "\\" RegistryKey
| project-reorder RegistryKey
| where RegistryKey has "Software\\Classes\\ms-settings\\shell\\open\\command"
| extend TimeKey = bin(TimeGenerated, 1h)
| join (
SecurityEvent
| where EventID == 4688
| where Process =~ "fodhelper.exe"
| where ParentProcessName endswith "cmd.exe" or ParentProcessName endswith "powershell.exe" or ParentProcessName endswith "powershell_ise.exe"
| extend TimeKey = bin(TimeGenerated, 1h)) on TimeKey, Computer
| extend HostName = tostring(split(Computer, ".")[0]), DomainIndex = toint(indexof(Computer, '.'))
| extend HostNameDomain = iff(DomainIndex != -1, substring(Computer, DomainIndex + 1), Computer)
| extend AccountName = tostring(split(TargetAccount, @'\')[1]), AccountNTDomain = tostring(split(TargetAccount, @'\')[0])
triggerOperator: gt
queryPeriod: 2h
OriginalUri: https://github.com/Azure/Azure-Sentinel/blob/master/Solutions/Windows Security Events/Analytic Rules/PotentialFodhelperUACBypass.yaml
relevantTechniques:
- T1548.002
status: Available
id: 56f3f35c-3aca-4437-a1fb-b7a84dc4af00
requiredDataConnectors:
- connectorId: SecurityEvents
dataTypes:
- SecurityEvent
- connectorId: WindowsSecurityEvents
dataTypes:
- SecurityEvent
version: 1.0.2
description: |
'This detection looks for the steps required to conduct a UAC bypass using Fodhelper.exe. By default this detection looks for the setting of the required registry keys and the invoking of the process within 1 hour - this can be tweaked as required.'
{
"$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/56f3f35c-3aca-4437-a1fb-b7a84dc4af00')]",
"kind": "Scheduled",
"name": "[concat(parameters('workspace'),'/Microsoft.SecurityInsights/56f3f35c-3aca-4437-a1fb-b7a84dc4af00')]",
"properties": {
"alertRuleTemplateName": "56f3f35c-3aca-4437-a1fb-b7a84dc4af00",
"customDetails": null,
"description": "'This detection looks for the steps required to conduct a UAC bypass using Fodhelper.exe. By default this detection looks for the setting of the required registry keys and the invoking of the process within 1 hour - this can be tweaked as required.'\n",
"displayName": "Potential Fodhelper UAC Bypass",
"enabled": true,
"entityMappings": [
{
"entityType": "Host",
"fieldMappings": [
{
"columnName": "Computer",
"identifier": "FullName"
},
{
"columnName": "HostName",
"identifier": "HostName"
},
{
"columnName": "HostNameDomain",
"identifier": "DnsDomain"
}
]
},
{
"entityType": "Account",
"fieldMappings": [
{
"columnName": "TargetAccount",
"identifier": "FullName"
},
{
"columnName": "AccountName",
"identifier": "Name"
},
{
"columnName": "AccountNTDomain",
"identifier": "NTDomain"
}
]
}
],
"OriginalUri": "https://github.com/Azure/Azure-Sentinel/blob/master/Solutions/Windows Security Events/Analytic Rules/PotentialFodhelperUACBypass.yaml",
"query": "SecurityEvent\n | where EventID == 4657\n | parse ObjectName with \"\\\\REGISTRY\\\\\" KeyPrefix \"\\\\\" RegistryKey\n | project-reorder RegistryKey\n | where RegistryKey has \"Software\\\\Classes\\\\ms-settings\\\\shell\\\\open\\\\command\"\n | extend TimeKey = bin(TimeGenerated, 1h)\n | join (\n SecurityEvent\n | where EventID == 4688\n | where Process =~ \"fodhelper.exe\"\n | where ParentProcessName endswith \"cmd.exe\" or ParentProcessName endswith \"powershell.exe\" or ParentProcessName endswith \"powershell_ise.exe\"\n | extend TimeKey = bin(TimeGenerated, 1h)) on TimeKey, Computer\n | extend HostName = tostring(split(Computer, \".\")[0]), DomainIndex = toint(indexof(Computer, '.'))\n | extend HostNameDomain = iff(DomainIndex != -1, substring(Computer, DomainIndex + 1), Computer)\n | extend AccountName = tostring(split(TargetAccount, @'\\')[1]), AccountNTDomain = tostring(split(TargetAccount, @'\\')[0])\n",
"queryFrequency": "PT2H",
"queryPeriod": "PT2H",
"severity": "Medium",
"status": "Available",
"subTechniques": [
"T1548.002"
],
"suppressionDuration": "PT1H",
"suppressionEnabled": false,
"tactics": [
"PrivilegeEscalation"
],
"techniques": [
"T1548"
],
"templateVersion": "1.0.2",
"triggerOperator": "GreaterThan",
"triggerThreshold": 0
},
"type": "Microsoft.OperationalInsights/workspaces/providers/alertRules"
}
]
}