Vectra AI Detect - Suspected Compromised Account
Id | 321f9dbd-64b7-4541-81dc-08cf7732ccb0 |
Rulename | Vectra AI Detect - Suspected Compromised Account |
Description | Create an incident when an Account is suspected to be compromised. The higher the severity level is, the more immediate attention it requires as Vectra AI engine is more confident that this is a real threat. Level of severity are: Low, Medium, High, Critical). Recommended configuration is to trigger an alert for at least High and Critical. |
Severity | Informational |
Tactics | CredentialAccess Discovery LateralMovement Collection CommandAndControl Exfiltration Impact |
Techniques | T1003 T1087 T1021 T1119 T1071 T1041 T1499 |
Required data connectors | AIVectraDetect AIVectraDetectAma CefAma |
Kind | Scheduled |
Query frequency | 5m |
Query period | 5m |
Trigger threshold | 0 |
Trigger operator | gt |
Source Uri | https://github.com/Azure/Azure-Sentinel/blob/master/Solutions/Vectra AI Detect/Analytic Rules/VectraDetect-Account-by-Severity.yaml |
Version | 1.0.8 |
Arm template | 321f9dbd-64b7-4541-81dc-08cf7732ccb0.json |
// Edit this variable to only keep the Severity level where an incident needs to be created.
//Level of severity are: Low, Medium, High, Critical). Recommended configuration is to trigger an alert for at least High and Critical.'
let configured_level = dynamic(["High", "Critical"]);
let upn_has_prefix = ":";
CommonSecurityLog
| where DeviceVendor == "Vectra Networks"
| where DeviceProduct == "X Series"
| where DeviceEventClassID == "asc"
| extend saccount = extract("saccount=(.+?);", 1, AdditionalExtensions)
| extend type = iff(saccount matches regex upn_has_prefix, tostring(split(saccount,":")[0]) ,"network" )
| extend upn = iff(saccount matches regex upn_has_prefix, tostring(split(saccount,":")[1]) , saccount )
| extend name = tostring(split(upn,"@")[0])
| extend upn_suffix = tostring(split(upn,"@")[1])
| project-rename threat_score = FlexNumber1
| project-rename certainty_score = FlexNumber2
| project-rename vectra_URL = DeviceCustomString4
| project-rename detection_name = DeviceEventClassID
| project-rename score_decreases = DeviceCustomString3
| extend level = case( threat_score < 50 and certainty_score < 50, "Low",
threat_score < 50 and certainty_score >= 50 , "Medium",
threat_score >= 50 and certainty_score <= 50, "High",
threat_score >= 50 and certainty_score >= 50, "Critical",
"UNKNOWN")
| extend Severity = case(level == "Info", "Informational",level == "Critical", "High", level)
| where level in (configured_level)
//keep only the event with the highest threat score per Host
| summarize arg_max(threat_score, *) by saccount
| sort by TimeGenerated
entityMappings:
- entityType: Account
fieldMappings:
- identifier: Name
columnName: name
- identifier: UPNSuffix
columnName: upn_suffix
name: Vectra AI Detect - Suspected Compromised Account
tactics:
- CredentialAccess
- Discovery
- LateralMovement
- Collection
- CommandAndControl
- Exfiltration
- Impact
severity: Informational
customDetails:
ScoreDecrease: score_decreases
triggerThreshold: 0
relevantTechniques:
- T1003
- T1087
- T1021
- T1119
- T1071
- T1041
- T1499
id: 321f9dbd-64b7-4541-81dc-08cf7732ccb0
version: 1.0.8
OriginalUri: https://github.com/Azure/Azure-Sentinel/blob/master/Solutions/Vectra AI Detect/Analytic Rules/VectraDetect-Account-by-Severity.yaml
incidentConfiguration:
createIncident: true
groupingConfiguration:
enabled: true
lookbackDuration: 7d
matchingMethod: AllEntities
reopenClosedIncident: true
queryFrequency: 5m
eventGroupingSettings:
aggregationKind: AlertPerResult
triggerOperator: gt
query: |
// Edit this variable to only keep the Severity level where an incident needs to be created.
//Level of severity are: Low, Medium, High, Critical). Recommended configuration is to trigger an alert for at least High and Critical.'
let configured_level = dynamic(["High", "Critical"]);
let upn_has_prefix = ":";
CommonSecurityLog
| where DeviceVendor == "Vectra Networks"
| where DeviceProduct == "X Series"
| where DeviceEventClassID == "asc"
| extend saccount = extract("saccount=(.+?);", 1, AdditionalExtensions)
| extend type = iff(saccount matches regex upn_has_prefix, tostring(split(saccount,":")[0]) ,"network" )
| extend upn = iff(saccount matches regex upn_has_prefix, tostring(split(saccount,":")[1]) , saccount )
| extend name = tostring(split(upn,"@")[0])
| extend upn_suffix = tostring(split(upn,"@")[1])
| project-rename threat_score = FlexNumber1
| project-rename certainty_score = FlexNumber2
| project-rename vectra_URL = DeviceCustomString4
| project-rename detection_name = DeviceEventClassID
| project-rename score_decreases = DeviceCustomString3
| extend level = case( threat_score < 50 and certainty_score < 50, "Low",
threat_score < 50 and certainty_score >= 50 , "Medium",
threat_score >= 50 and certainty_score <= 50, "High",
threat_score >= 50 and certainty_score >= 50, "Critical",
"UNKNOWN")
| extend Severity = case(level == "Info", "Informational",level == "Critical", "High", level)
| where level in (configured_level)
//keep only the event with the highest threat score per Host
| summarize arg_max(threat_score, *) by saccount
| sort by TimeGenerated
description: |
'Create an incident when an Account is suspected to be compromised.
The higher the severity level is, the more immediate attention it requires as Vectra AI engine is more confident that this is a real threat.
Level of severity are: Low, Medium, High, Critical). Recommended configuration is to trigger an alert for at least High and Critical.'
requiredDataConnectors:
- connectorId: AIVectraDetect
dataTypes:
- CommonSecurityLog
- connectorId: AIVectraDetectAma
dataTypes:
- CommonSecurityLog
- connectorId: CefAma
dataTypes:
- CommonSecurityLog
status: Available
queryPeriod: 5m
alertDetailsOverride:
alertSeverityColumnName: Severity
alertDescriptionFormat: |
The account {{saccount}} has a threat score of {{threat_score}} and a
certainty of {{certainty_score}}
alertDisplayNameFormat: Vectra AI Detect - Account {{saccount}} reaches {{level}} severity
alertDynamicProperties:
- alertProperty: AlertLink
value: vectra_URL
- alertProperty: ProductName
value: DeviceProduct
- alertProperty: ProviderName
value: DeviceVendor
- alertProperty: ConfidenceScore
value: certainty_score
kind: Scheduled
{
"$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/321f9dbd-64b7-4541-81dc-08cf7732ccb0')]",
"kind": "Scheduled",
"name": "[concat(parameters('workspace'),'/Microsoft.SecurityInsights/321f9dbd-64b7-4541-81dc-08cf7732ccb0')]",
"properties": {
"alertDetailsOverride": {
"alertDescriptionFormat": "The account {{saccount}} has a threat score of {{threat_score}} and a\ncertainty of {{certainty_score}}\n",
"alertDisplayNameFormat": "Vectra AI Detect - Account {{saccount}} reaches {{level}} severity",
"alertDynamicProperties": [
{
"alertProperty": "AlertLink",
"value": "vectra_URL"
},
{
"alertProperty": "ProductName",
"value": "DeviceProduct"
},
{
"alertProperty": "ProviderName",
"value": "DeviceVendor"
},
{
"alertProperty": "ConfidenceScore",
"value": "certainty_score"
}
],
"alertSeverityColumnName": "Severity"
},
"alertRuleTemplateName": "321f9dbd-64b7-4541-81dc-08cf7732ccb0",
"customDetails": {
"ScoreDecrease": "score_decreases"
},
"description": "'Create an incident when an Account is suspected to be compromised. \nThe higher the severity level is, the more immediate attention it requires as Vectra AI engine is more confident that this is a real threat. \nLevel of severity are: Low, Medium, High, Critical). Recommended configuration is to trigger an alert for at least High and Critical.'\n",
"displayName": "Vectra AI Detect - Suspected Compromised Account",
"enabled": true,
"entityMappings": [
{
"entityType": "Account",
"fieldMappings": [
{
"columnName": "name",
"identifier": "Name"
},
{
"columnName": "upn_suffix",
"identifier": "UPNSuffix"
}
]
}
],
"eventGroupingSettings": {
"aggregationKind": "AlertPerResult"
},
"incidentConfiguration": {
"createIncident": true,
"groupingConfiguration": {
"enabled": true,
"lookbackDuration": "P7D",
"matchingMethod": "AllEntities",
"reopenClosedIncident": true
}
},
"OriginalUri": "https://github.com/Azure/Azure-Sentinel/blob/master/Solutions/Vectra AI Detect/Analytic Rules/VectraDetect-Account-by-Severity.yaml",
"query": "// Edit this variable to only keep the Severity level where an incident needs to be created.\n//Level of severity are: Low, Medium, High, Critical). Recommended configuration is to trigger an alert for at least High and Critical.'\nlet configured_level = dynamic([\"High\", \"Critical\"]);\nlet upn_has_prefix = \":\";\nCommonSecurityLog\n| where DeviceVendor == \"Vectra Networks\"\n| where DeviceProduct == \"X Series\"\n| where DeviceEventClassID == \"asc\"\n| extend saccount = extract(\"saccount=(.+?);\", 1, AdditionalExtensions)\n| extend type = iff(saccount matches regex upn_has_prefix, tostring(split(saccount,\":\")[0]) ,\"network\" ) \n| extend upn = iff(saccount matches regex upn_has_prefix, tostring(split(saccount,\":\")[1]) , saccount )\n| extend name = tostring(split(upn,\"@\")[0])\n| extend upn_suffix = tostring(split(upn,\"@\")[1])\n| project-rename threat_score = FlexNumber1\n| project-rename certainty_score = FlexNumber2\n| project-rename vectra_URL = DeviceCustomString4\n| project-rename detection_name = DeviceEventClassID\n| project-rename score_decreases = DeviceCustomString3\n| extend level = case( threat_score < 50 and certainty_score < 50, \"Low\",\n threat_score < 50 and certainty_score >= 50 , \"Medium\", \n threat_score >= 50 and certainty_score <= 50, \"High\", \n threat_score >= 50 and certainty_score >= 50, \"Critical\",\n \"UNKNOWN\")\n| extend Severity = case(level == \"Info\", \"Informational\",level == \"Critical\", \"High\", level)\n| where level in (configured_level) \n//keep only the event with the highest threat score per Host\n| summarize arg_max(threat_score, *) by saccount\n| sort by TimeGenerated\n",
"queryFrequency": "PT5M",
"queryPeriod": "PT5M",
"severity": "Informational",
"status": "Available",
"subTechniques": [],
"suppressionDuration": "PT1H",
"suppressionEnabled": false,
"tactics": [
"Collection",
"CommandAndControl",
"CredentialAccess",
"Discovery",
"Exfiltration",
"Impact",
"LateralMovement"
],
"techniques": [
"T1003",
"T1021",
"T1041",
"T1071",
"T1087",
"T1119",
"T1499"
],
"templateVersion": "1.0.8",
"triggerOperator": "GreaterThan",
"triggerThreshold": 0
},
"type": "Microsoft.OperationalInsights/workspaces/providers/alertRules"
}
]
}