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), '\\'))
OriginalUri: https://github.com/Azure/Azure-Sentinel/blob/master/Solutions/Malware Protection Essentials/Analytic Rules/WindowsAllowFirewallRuleAdded.yaml
status: Available
id: 056593d4-ca3b-47a7-be9d-d1d0884a1d36
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}}
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), '\\'))
tags:
- SchemaVersion: 0.1.2
Schema: _ASim_RegistryEvent
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.
name: Detect Windows Allow Firewall Rule Addition/Modification
relevantTechniques:
- T1562
entityMappings:
- entityType: Host
fieldMappings:
- identifier: HostName
columnName: HostName
- identifier: DnsDomain
columnName: DnsDomain
- identifier: NTDomain
columnName: NTDomain
- entityType: Account
fieldMappings:
- identifier: Name
columnName: Username
- identifier: UPNSuffix
columnName: UPNSuffix
- identifier: NTDomain
columnName: NTDomain
- entityType: Process
fieldMappings:
- identifier: ProcessId
columnName: ActingProcessId
- identifier: CommandLine
columnName: ActingProcessCommandLine
- entityType: RegistryKey
fieldMappings:
- identifier: Hive
columnName: RegHive
- identifier: Key
columnName: RegKey
- entityType: RegistryValue
fieldMappings:
- identifier: Name
columnName: RegistryValue
- identifier: Value
columnName: RegistryValueData
- identifier: ValueType
columnName: RegistryValueType
triggerThreshold: 0
severity: Medium
requiredDataConnectors:
- dataTypes:
- CommonSecurityLog
connectorId: CrowdStrikeFalconEndpointProtection
- dataTypes:
- SecurityAlert
connectorId: MicrosoftThreatProtection
- dataTypes:
- SentinelOne_CL
connectorId: SentinelOne
- dataTypes:
- CarbonBlackEvents_CL
connectorId: VMwareCarbonBlack
- dataTypes:
- CiscoSecureEndpoint_CL
connectorId: CiscoSecureEndpoint
- dataTypes:
- TMApexOneEvent
connectorId: TrendMicroApexOne
- dataTypes:
- TMApexOneEvent
connectorId: TrendMicroApexOneAma
eventGroupingSettings:
aggregationKind: singleAlert
queryFrequency: 1h
queryPeriod: 1h
version: 1.0.0
kind: Scheduled
tactics:
- DefenseEvasion
triggerOperator: gt
{
"$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"
}
]
}