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 | CrowdStrikeFalconEndpointProtection |
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 | 1.0.1 |
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"
triggerOperator: gt
version: 1.0.1
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"
status: Available
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
queryFrequency: 1h
requiredDataConnectors:
- connectorId: CrowdStrikeFalconEndpointProtection
dataTypes:
- CommonSecurityLog
name: Critical or High Severity Detections by User
queryPeriod: 1h
severity: High
kind: Scheduled
tactics:
id: 4465ebde-b381-45f7-ad08-7d818070a11c
description: |
'Creates an incident when a large number of Critical/High severity CrowdStrike Falcon sensor detections is triggered by a single user'
relevantTechniques:
triggerThreshold: 0
{
"$schema": "https://schema.management.azure.com/schemas/2019-04-01/deploymentTemplate.json#",
"contentVersion": "1.0.0.0",
"parameters": {
"workspace": {
"type": "String"
}
},
"resources": [
{
"id": "[concat(resourceId('Microsoft.OperationalInsights/workspaces/providers', parameters('workspace'), 'Microsoft.SecurityInsights'),'/alertRules/4465ebde-b381-45f7-ad08-7d818070a11c')]",
"name": "[concat(parameters('workspace'),'/Microsoft.SecurityInsights/4465ebde-b381-45f7-ad08-7d818070a11c')]",
"type": "Microsoft.OperationalInsights/workspaces/providers/alertRules",
"kind": "Scheduled",
"apiVersion": "2022-11-01-preview",
"properties": {
"displayName": "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'\n",
"severity": "High",
"enabled": true,
"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",
"triggerOperator": "GreaterThan",
"triggerThreshold": 0,
"suppressionDuration": "PT1H",
"suppressionEnabled": false,
"tactics": null,
"techniques": null,
"alertRuleTemplateName": "4465ebde-b381-45f7-ad08-7d818070a11c",
"customDetails": null,
"entityMappings": [
{
"fieldMappings": [
{
"columnName": "AccountCustomEntity",
"identifier": "FullName"
}
],
"entityType": "Account"
},
{
"fieldMappings": [
{
"columnName": "HostCustomEntity",
"identifier": "FullName"
}
],
"entityType": "Host"
},
{
"fieldMappings": [
{
"columnName": "IPCustomEntity",
"identifier": "Address"
}
],
"entityType": "IP"
},
{
"fieldMappings": [
{
"columnName": "FileHashAlgo",
"identifier": "Algorithm"
},
{
"columnName": "FileHashCustomEntity",
"identifier": "Value"
}
],
"entityType": "FileHash"
}
],
"OriginalUri": "https://github.com/Azure/Azure-Sentinel/blob/master/Solutions/CrowdStrike Falcon Endpoint Protection/Analytic Rules/CriticalOrHighSeverityDetectionsByUser.yaml",
"status": "Available",
"templateVersion": "1.0.1"
}
}
]
}