Detect Windows Allow Firewall Rule AdditionModification
| Id | 056593d4-ca3b-47a7-be9d-d1d0884a1d36 |
| Rulename | Detect Windows Allow Firewall Rule Addition/Modification |
| Description | This analytic rule detects any registry value creation or modification of Windows firewall registry keys to allow network traffic. This could be an indication of defense evasion by an adversary to allow network traffic to/from a compromised host. |
| Severity | Medium |
| Tactics | DefenseEvasion |
| Techniques | T1562 |
| Required data connectors | CiscoSecureEndpoint CrowdStrikeFalconEndpointProtection MicrosoftThreatProtection SentinelOne TrendMicroApexOne TrendMicroApexOneAma VMwareCarbonBlack |
| 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/Malware Protection Essentials/Analytic Rules/WindowsAllowFirewallRuleAdded.yaml |
| Version | 1.0.0 |
| Arm template | 056593d4-ca3b-47a7-be9d-d1d0884a1d36.json |
// List of Windows Firewall registry keys to monitor
let firewallRegistryList = dynamic([
'HKEY_LOCAL_MACHINE\\SYSTEM\\CurrentControlSet\\Services\\SharedAccess\\Parameters\\FirewallPolicy\\RestrictedServices\\Static\\System',
'HKEY_LOCAL_MACHINE\\SYSTEM\\CurrentControlSet\\Services\\SharedAccess\\Parameters\\FirewallPolicy\\RestrictedServices\\Configurable\\System',
'HKEY_LOCAL_MACHINE\\SYSTEM\\CurrentControlSet\\Services\\SharedAccess\\Defaults\\FirewallPolicy\\FirewallRules',
'HKEY_LOCAL_MACHINE\\SOFTWARE\\Policies\\Microsoft\\WindowsFirewall'
]);
_ASim_RegistryEvent
| where EventType in ('RegistryValueSet', 'RegistryKeyCreated')
| where RegistryKey has_any (firewallRegistryList) and RegistryValueData has_all ('Action=Allow', 'Active=TRUE')
| project
TimeGenerated,
DvcHostname,
ActorUsername,
ActorUsernameType,
ActingProcessId,
ActingProcessName,
ActingProcessCommandLine,
RegistryKey,
RegistryValue,
RegistryValueType,
RegistryValueData
| extend HostName = tostring(split(DvcHostname, '.')[0])
| extend DnsDomain = tostring(strcat_array(array_slice(split(DvcHostname, '.'), 1, -1), '.'))
| extend Username = iff(tostring(ActorUsernameType) == 'Windows', tostring(split(ActorUsername, '\\')[1]), ActorUsername)
| extend NTDomain = iff(tostring(ActorUsernameType) == 'Windows', tostring(split(ActorUsername, '\\')[0]), ActorUsername)
| extend Username = iff(tostring(ActorUsernameType) == 'UPN', tostring(split(ActorUsername, '@')[0]), Username)
| extend UPNSuffix = iff(tostring(ActorUsernameType) == 'UPN', tostring(split(ActorUsername, '@')[1]), '')
| extend RegHive = tostring(split(RegistryKey, '\\')[0]), RegKey = tostring(strcat_array(array_slice(split(RegistryKey, '\\'), 1, -1), '\\'))
id: 056593d4-ca3b-47a7-be9d-d1d0884a1d36
tactics:
- DefenseEvasion
queryPeriod: 1h
OriginalUri: https://github.com/Azure/Azure-Sentinel/blob/master/Solutions/Malware Protection Essentials/Analytic Rules/WindowsAllowFirewallRuleAdded.yaml
eventGroupingSettings:
aggregationKind: singleAlert
triggerThreshold: 0
name: Detect Windows Allow Firewall Rule Addition/Modification
query: |
// List of Windows Firewall registry keys to monitor
let firewallRegistryList = dynamic([
'HKEY_LOCAL_MACHINE\\SYSTEM\\CurrentControlSet\\Services\\SharedAccess\\Parameters\\FirewallPolicy\\RestrictedServices\\Static\\System',
'HKEY_LOCAL_MACHINE\\SYSTEM\\CurrentControlSet\\Services\\SharedAccess\\Parameters\\FirewallPolicy\\RestrictedServices\\Configurable\\System',
'HKEY_LOCAL_MACHINE\\SYSTEM\\CurrentControlSet\\Services\\SharedAccess\\Defaults\\FirewallPolicy\\FirewallRules',
'HKEY_LOCAL_MACHINE\\SOFTWARE\\Policies\\Microsoft\\WindowsFirewall'
]);
_ASim_RegistryEvent
| where EventType in ('RegistryValueSet', 'RegistryKeyCreated')
| where RegistryKey has_any (firewallRegistryList) and RegistryValueData has_all ('Action=Allow', 'Active=TRUE')
| project
TimeGenerated,
DvcHostname,
ActorUsername,
ActorUsernameType,
ActingProcessId,
ActingProcessName,
ActingProcessCommandLine,
RegistryKey,
RegistryValue,
RegistryValueType,
RegistryValueData
| extend HostName = tostring(split(DvcHostname, '.')[0])
| extend DnsDomain = tostring(strcat_array(array_slice(split(DvcHostname, '.'), 1, -1), '.'))
| extend Username = iff(tostring(ActorUsernameType) == 'Windows', tostring(split(ActorUsername, '\\')[1]), ActorUsername)
| extend NTDomain = iff(tostring(ActorUsernameType) == 'Windows', tostring(split(ActorUsername, '\\')[0]), ActorUsername)
| extend Username = iff(tostring(ActorUsernameType) == 'UPN', tostring(split(ActorUsername, '@')[0]), Username)
| extend UPNSuffix = iff(tostring(ActorUsernameType) == 'UPN', tostring(split(ActorUsername, '@')[1]), '')
| extend RegHive = tostring(split(RegistryKey, '\\')[0]), RegKey = tostring(strcat_array(array_slice(split(RegistryKey, '\\'), 1, -1), '\\'))
severity: Medium
triggerOperator: gt
kind: Scheduled
relevantTechniques:
- T1562
tags:
- SchemaVersion: 0.1.2
Schema: _ASim_RegistryEvent
queryFrequency: 1h
requiredDataConnectors:
- connectorId: CrowdStrikeFalconEndpointProtection
dataTypes:
- CommonSecurityLog
- connectorId: MicrosoftThreatProtection
dataTypes:
- SecurityAlert
- connectorId: SentinelOne
dataTypes:
- SentinelOne_CL
- connectorId: VMwareCarbonBlack
dataTypes:
- CarbonBlackEvents_CL
- connectorId: CiscoSecureEndpoint
dataTypes:
- CiscoSecureEndpoint_CL
- connectorId: TrendMicroApexOne
dataTypes:
- TMApexOneEvent
- connectorId: TrendMicroApexOneAma
dataTypes:
- TMApexOneEvent
version: 1.0.0
description: |
This analytic rule detects any registry value creation or modification of Windows firewall registry keys to allow network traffic. This could be an indication of defense evasion by an adversary to allow network traffic to/from a compromised host.
status: Available
alertDetailsOverride:
alertDisplayNameFormat: Allow Firewall Rule {{RegistryValueData}} added at registry key {{RegKey}} on {{HostName}}
alertDescriptionFormat: An allow Firewall Rule {{RegistryValueData}} added at registry key {{RegKey}} by {{Username}}.
entityMappings:
- fieldMappings:
- columnName: HostName
identifier: HostName
- columnName: DnsDomain
identifier: DnsDomain
- columnName: NTDomain
identifier: NTDomain
entityType: Host
- fieldMappings:
- columnName: Username
identifier: Name
- columnName: UPNSuffix
identifier: UPNSuffix
- columnName: NTDomain
identifier: NTDomain
entityType: Account
- fieldMappings:
- columnName: ActingProcessId
identifier: ProcessId
- columnName: ActingProcessCommandLine
identifier: CommandLine
entityType: Process
- fieldMappings:
- columnName: RegHive
identifier: Hive
- columnName: RegKey
identifier: Key
entityType: RegistryKey
- fieldMappings:
- columnName: RegistryValue
identifier: Name
- columnName: RegistryValueData
identifier: Value
- columnName: RegistryValueType
identifier: ValueType
entityType: RegistryValue
{
"$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/056593d4-ca3b-47a7-be9d-d1d0884a1d36')]",
"kind": "Scheduled",
"name": "[concat(parameters('workspace'),'/Microsoft.SecurityInsights/056593d4-ca3b-47a7-be9d-d1d0884a1d36')]",
"properties": {
"alertDetailsOverride": {
"alertDescriptionFormat": "An allow Firewall Rule {{RegistryValueData}} added at registry key {{RegKey}} by {{Username}}.",
"alertDisplayNameFormat": "Allow Firewall Rule {{RegistryValueData}} added at registry key {{RegKey}} on {{HostName}}"
},
"alertRuleTemplateName": "056593d4-ca3b-47a7-be9d-d1d0884a1d36",
"customDetails": null,
"description": "This analytic rule detects any registry value creation or modification of Windows firewall registry keys to allow network traffic. This could be an indication of defense evasion by an adversary to allow network traffic to/from a compromised host.\n",
"displayName": "Detect Windows Allow Firewall Rule Addition/Modification",
"enabled": true,
"entityMappings": [
{
"entityType": "Host",
"fieldMappings": [
{
"columnName": "HostName",
"identifier": "HostName"
},
{
"columnName": "DnsDomain",
"identifier": "DnsDomain"
},
{
"columnName": "NTDomain",
"identifier": "NTDomain"
}
]
},
{
"entityType": "Account",
"fieldMappings": [
{
"columnName": "Username",
"identifier": "Name"
},
{
"columnName": "UPNSuffix",
"identifier": "UPNSuffix"
},
{
"columnName": "NTDomain",
"identifier": "NTDomain"
}
]
},
{
"entityType": "Process",
"fieldMappings": [
{
"columnName": "ActingProcessId",
"identifier": "ProcessId"
},
{
"columnName": "ActingProcessCommandLine",
"identifier": "CommandLine"
}
]
},
{
"entityType": "RegistryKey",
"fieldMappings": [
{
"columnName": "RegHive",
"identifier": "Hive"
},
{
"columnName": "RegKey",
"identifier": "Key"
}
]
},
{
"entityType": "RegistryValue",
"fieldMappings": [
{
"columnName": "RegistryValue",
"identifier": "Name"
},
{
"columnName": "RegistryValueData",
"identifier": "Value"
},
{
"columnName": "RegistryValueType",
"identifier": "ValueType"
}
]
}
],
"eventGroupingSettings": {
"aggregationKind": "singleAlert"
},
"OriginalUri": "https://github.com/Azure/Azure-Sentinel/blob/master/Solutions/Malware Protection Essentials/Analytic Rules/WindowsAllowFirewallRuleAdded.yaml",
"query": "// List of Windows Firewall registry keys to monitor\nlet firewallRegistryList = dynamic([\n 'HKEY_LOCAL_MACHINE\\\\SYSTEM\\\\CurrentControlSet\\\\Services\\\\SharedAccess\\\\Parameters\\\\FirewallPolicy\\\\RestrictedServices\\\\Static\\\\System',\n 'HKEY_LOCAL_MACHINE\\\\SYSTEM\\\\CurrentControlSet\\\\Services\\\\SharedAccess\\\\Parameters\\\\FirewallPolicy\\\\RestrictedServices\\\\Configurable\\\\System',\n 'HKEY_LOCAL_MACHINE\\\\SYSTEM\\\\CurrentControlSet\\\\Services\\\\SharedAccess\\\\Defaults\\\\FirewallPolicy\\\\FirewallRules',\n 'HKEY_LOCAL_MACHINE\\\\SOFTWARE\\\\Policies\\\\Microsoft\\\\WindowsFirewall'\n ]);\n_ASim_RegistryEvent\n| where EventType in ('RegistryValueSet', 'RegistryKeyCreated') \n| where RegistryKey has_any (firewallRegistryList) and RegistryValueData has_all ('Action=Allow', 'Active=TRUE')\n| project\n TimeGenerated,\n DvcHostname,\n ActorUsername,\n ActorUsernameType,\n ActingProcessId,\n ActingProcessName,\n ActingProcessCommandLine,\n RegistryKey,\n RegistryValue,\n RegistryValueType,\n RegistryValueData\n| extend HostName = tostring(split(DvcHostname, '.')[0])\n| extend DnsDomain = tostring(strcat_array(array_slice(split(DvcHostname, '.'), 1, -1), '.'))\n| extend Username = iff(tostring(ActorUsernameType) == 'Windows', tostring(split(ActorUsername, '\\\\')[1]), ActorUsername)\n| extend NTDomain = iff(tostring(ActorUsernameType) == 'Windows', tostring(split(ActorUsername, '\\\\')[0]), ActorUsername)\n| extend Username = iff(tostring(ActorUsernameType) == 'UPN', tostring(split(ActorUsername, '@')[0]), Username)\n| extend UPNSuffix = iff(tostring(ActorUsernameType) == 'UPN', tostring(split(ActorUsername, '@')[1]), '')\n| extend RegHive = tostring(split(RegistryKey, '\\\\')[0]), RegKey = tostring(strcat_array(array_slice(split(RegistryKey, '\\\\'), 1, -1), '\\\\')) \n",
"queryFrequency": "PT1H",
"queryPeriod": "PT1H",
"severity": "Medium",
"status": "Available",
"subTechniques": [],
"suppressionDuration": "PT1H",
"suppressionEnabled": false,
"tactics": [
"DefenseEvasion"
],
"tags": [
{
"Schema": "_ASim_RegistryEvent",
"SchemaVersion": "0.1.2"
}
],
"techniques": [
"T1562"
],
"templateVersion": "1.0.0",
"triggerOperator": "GreaterThan",
"triggerThreshold": 0
},
"type": "Microsoft.OperationalInsights/workspaces/providers/alertRules"
}
]
}