Critical or High Severity Detections by User
Id | 4465ebde-b381-45f7-ad08-7d818070a11c |
Rulename | Critical or High Severity Detections by User |
Description | Creates an incident when a large number of Critical/High severity CrowdStrike Falcon sensor detections is triggered by a single user |
Severity | High |
Required data connectors | CefAma |
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/CrowdStrike Falcon Endpoint Protection/Analytic Rules/CriticalOrHighSeverityDetectionsByUser.yaml |
Version | 1.0.4 |
Arm template | 4465ebde-b381-45f7-ad08-7d818070a11c.json |
let timeframe = 1h;
let threshold = 15; // update threshold value based on organization's preference
let NoteableEvents = CrowdStrikeFalconEventStream
| where TimeGenerated > ago(timeframe)
| where EventType == "DetectionSummaryEvent"
| where Severity in ("Critical", "High")
| summarize Total = count() by DstUserName
| where Total > threshold;
CrowdStrikeFalconEventStream
| where TimeGenerated > ago(timeframe)
| where EventType == "DetectionSummaryEvent"
| where Severity in ("Critical", "High")
| join kind=inner (NoteableEvents) on DstUserName
| summarize StartTimeUtc = min(TimeGenerated), EndTimeUtc = max(TimeGenerated), Total = count() by DstHostName, SrcIpAddr, DstUserName, FileName, FileHash, Message
| extend timestamp = StartTimeUtc, AccountCustomEntity = DstUserName, HostCustomEntity = DstHostName, IPCustomEntity = SrcIpAddr, FileHashCustomEntity = FileHash, FileHashAlgo = "MD5"
name: Critical or High Severity Detections by User
version: 1.0.4
severity: High
queryFrequency: 1h
triggerOperator: gt
relevantTechniques: []
status: Available
description: |
'Creates an incident when a large number of Critical/High severity CrowdStrike Falcon sensor detections is triggered by a single user'
OriginalUri: https://github.com/Azure/Azure-Sentinel/blob/master/Solutions/CrowdStrike Falcon Endpoint Protection/Analytic Rules/CriticalOrHighSeverityDetectionsByUser.yaml
requiredDataConnectors:
- connectorId: CefAma
dataTypes:
- CommonSecurityLog
entityMappings:
- fieldMappings:
- identifier: FullName
columnName: AccountCustomEntity
entityType: Account
- fieldMappings:
- identifier: FullName
columnName: HostCustomEntity
entityType: Host
- fieldMappings:
- identifier: Address
columnName: IPCustomEntity
entityType: IP
- fieldMappings:
- identifier: Algorithm
columnName: FileHashAlgo
- identifier: Value
columnName: FileHashCustomEntity
entityType: FileHash
tactics: []
queryPeriod: 1h
query: |
let timeframe = 1h;
let threshold = 15; // update threshold value based on organization's preference
let NoteableEvents = CrowdStrikeFalconEventStream
| where TimeGenerated > ago(timeframe)
| where EventType == "DetectionSummaryEvent"
| where Severity in ("Critical", "High")
| summarize Total = count() by DstUserName
| where Total > threshold;
CrowdStrikeFalconEventStream
| where TimeGenerated > ago(timeframe)
| where EventType == "DetectionSummaryEvent"
| where Severity in ("Critical", "High")
| join kind=inner (NoteableEvents) on DstUserName
| summarize StartTimeUtc = min(TimeGenerated), EndTimeUtc = max(TimeGenerated), Total = count() by DstHostName, SrcIpAddr, DstUserName, FileName, FileHash, Message
| extend timestamp = StartTimeUtc, AccountCustomEntity = DstUserName, HostCustomEntity = DstHostName, IPCustomEntity = SrcIpAddr, FileHashCustomEntity = FileHash, FileHashAlgo = "MD5"
kind: Scheduled
triggerThreshold: 0
id: 4465ebde-b381-45f7-ad08-7d818070a11c
{
"$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/4465ebde-b381-45f7-ad08-7d818070a11c')]",
"kind": "Scheduled",
"name": "[concat(parameters('workspace'),'/Microsoft.SecurityInsights/4465ebde-b381-45f7-ad08-7d818070a11c')]",
"properties": {
"alertRuleTemplateName": "4465ebde-b381-45f7-ad08-7d818070a11c",
"customDetails": null,
"description": "'Creates an incident when a large number of Critical/High severity CrowdStrike Falcon sensor detections is triggered by a single user'\n",
"displayName": "Critical or High Severity Detections by User",
"enabled": true,
"entityMappings": [
{
"entityType": "Account",
"fieldMappings": [
{
"columnName": "AccountCustomEntity",
"identifier": "FullName"
}
]
},
{
"entityType": "Host",
"fieldMappings": [
{
"columnName": "HostCustomEntity",
"identifier": "FullName"
}
]
},
{
"entityType": "IP",
"fieldMappings": [
{
"columnName": "IPCustomEntity",
"identifier": "Address"
}
]
},
{
"entityType": "FileHash",
"fieldMappings": [
{
"columnName": "FileHashAlgo",
"identifier": "Algorithm"
},
{
"columnName": "FileHashCustomEntity",
"identifier": "Value"
}
]
}
],
"OriginalUri": "https://github.com/Azure/Azure-Sentinel/blob/master/Solutions/CrowdStrike Falcon Endpoint Protection/Analytic Rules/CriticalOrHighSeverityDetectionsByUser.yaml",
"query": "let timeframe = 1h;\nlet threshold = 15; // update threshold value based on organization's preference\nlet NoteableEvents = CrowdStrikeFalconEventStream\n| where TimeGenerated > ago(timeframe)\n| where EventType == \"DetectionSummaryEvent\"\n| where Severity in (\"Critical\", \"High\")\n| summarize Total = count() by DstUserName\n| where Total > threshold;\nCrowdStrikeFalconEventStream\n| where TimeGenerated > ago(timeframe)\n| where EventType == \"DetectionSummaryEvent\"\n| where Severity in (\"Critical\", \"High\")\n| join kind=inner (NoteableEvents) on DstUserName\n| summarize StartTimeUtc = min(TimeGenerated), EndTimeUtc = max(TimeGenerated), Total = count() by DstHostName, SrcIpAddr, DstUserName, FileName, FileHash, Message\n| extend timestamp = StartTimeUtc, AccountCustomEntity = DstUserName, HostCustomEntity = DstHostName, IPCustomEntity = SrcIpAddr, FileHashCustomEntity = FileHash, FileHashAlgo = \"MD5\"\n",
"queryFrequency": "PT1H",
"queryPeriod": "PT1H",
"severity": "High",
"status": "Available",
"subTechniques": [],
"suppressionDuration": "PT1H",
"suppressionEnabled": false,
"tactics": [],
"techniques": [],
"templateVersion": "1.0.4",
"triggerOperator": "GreaterThan",
"triggerThreshold": 0
},
"type": "Microsoft.OperationalInsights/workspaces/providers/alertRules"
}
]
}