Suspicious Sign In by Entra ID Connect Sync Account
| Id | 2cd8b3d5-c9e0-4be3-80f7-0469d511c3f6 |
| Rulename | Suspicious Sign In by Entra ID Connect Sync Account |
| Description | This query looks for sign ins by the Microsoft Entra ID Connect Sync account to Azure where properties about the logon are anomalous. This query uses Microsoft Sentinel’s UEBA features to detect these suspicious properties. A threat actor may attempt to steal the Sync account credentials and use them to access Azure resources. This alert should be reviewed to ensure that the log in came was from a legitimate source. |
| Severity | Medium |
| Tactics | InitialAccess |
| Techniques | T1078.004 |
| Required data connectors | BehaviorAnalytics |
| Kind | Scheduled |
| Query frequency | 1h |
| Query period | 1h |
| Trigger threshold | 0 |
| Trigger operator | gt |
| Source Uri | https://github.com/Azure/Azure-Sentinel/blob/master/Detections/BehaviorAnalytics/SuspiciousSigninByAADConnectAccount.yaml |
| Version | 1.0.3 |
| Arm template | 2cd8b3d5-c9e0-4be3-80f7-0469d511c3f6.json |
BehaviorAnalytics
// User modification is expected from this account so focus on logons
| where ActivityType =~ "LogOn"
| where UserName startswith "Sync_" and UsersInsights.AccountDisplayName =~ "On-Premises Directory Synchronization Service Account"
// Filter out this expected activity
| where ActivityInsights.App !~ "Microsoft Azure Active Directory Connect"
| where InvestigationPriority > 0
| extend Name = split(UserPrincipalName, "@")[0], UPNSuffix = split(UserPrincipalName, "@")[1]
kind: Scheduled
relevantTechniques:
- T1078.004
metadata:
support:
tier: Community
author:
name: Microsoft Security Community
categories:
domains:
- Identity
- Security - Threat Protection
source:
kind: Community
description: |
'This query looks for sign ins by the Microsoft Entra ID Connect Sync account to Azure where properties about the logon are anomalous.
This query uses Microsoft Sentinel's UEBA features to detect these suspicious properties.
A threat actor may attempt to steal the Sync account credentials and use them to access Azure resources. This alert should be
reviewed to ensure that the log in came was from a legitimate source.'
queryPeriod: 1h
queryFrequency: 1h
tactics:
- InitialAccess
name: Suspicious Sign In by Entra ID Connect Sync Account
requiredDataConnectors:
- connectorId: BehaviorAnalytics
dataTypes:
- BehaviorAnalytics
alertDetailsOverride:
alertDisplayNameFormat: Suspicious Sign In by AAD Connect Sync Account {{UserPrincipalName}} from {{SourceIPAddress}}
alertDescriptionFormat: |
This query looks for sign ins by the Azure AD Connect Sync account to Azure where properties about the logon are anomalous.
This query uses Microsoft Sentinel's UEBA features to detect these suspicious properties.
A threat actor may attempt to steal the Sync account credentials and use them to access Azure resources. This alert should be
reviewed to ensure that the log in came was from a legitimate source.
In this case {{UserPrincipalName}} logged in from {{SourceIPAddress}}.
entityMappings:
- entityType: Account
fieldMappings:
- identifier: FullName
columnName: UserPrincipalName
- identifier: Name
columnName: Name
- identifier: UPNSuffix
columnName: UPNSuffix
- entityType: IP
fieldMappings:
- identifier: Address
columnName: SourceIPAddress
- entityType: Host
fieldMappings:
- identifier: HostName
columnName: DestinationDevice
triggerThreshold: 0
version: 1.0.3
id: 2cd8b3d5-c9e0-4be3-80f7-0469d511c3f6
query: |
BehaviorAnalytics
// User modification is expected from this account so focus on logons
| where ActivityType =~ "LogOn"
| where UserName startswith "Sync_" and UsersInsights.AccountDisplayName =~ "On-Premises Directory Synchronization Service Account"
// Filter out this expected activity
| where ActivityInsights.App !~ "Microsoft Azure Active Directory Connect"
| where InvestigationPriority > 0
| extend Name = split(UserPrincipalName, "@")[0], UPNSuffix = split(UserPrincipalName, "@")[1]
status: Available
triggerOperator: gt
OriginalUri: https://github.com/Azure/Azure-Sentinel/blob/master/Detections/BehaviorAnalytics/SuspiciousSigninByAADConnectAccount.yaml
severity: Medium
{
"$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/2cd8b3d5-c9e0-4be3-80f7-0469d511c3f6')]",
"kind": "Scheduled",
"name": "[concat(parameters('workspace'),'/Microsoft.SecurityInsights/2cd8b3d5-c9e0-4be3-80f7-0469d511c3f6')]",
"properties": {
"alertDetailsOverride": {
"alertDescriptionFormat": "This query looks for sign ins by the Azure AD Connect Sync account to Azure where properties about the logon are anomalous.\nThis query uses Microsoft Sentinel's UEBA features to detect these suspicious properties.\nA threat actor may attempt to steal the Sync account credentials and use them to access Azure resources. This alert should be \nreviewed to ensure that the log in came was from a legitimate source.\nIn this case {{UserPrincipalName}} logged in from {{SourceIPAddress}}.\n",
"alertDisplayNameFormat": "Suspicious Sign In by AAD Connect Sync Account {{UserPrincipalName}} from {{SourceIPAddress}}"
},
"alertRuleTemplateName": "2cd8b3d5-c9e0-4be3-80f7-0469d511c3f6",
"customDetails": null,
"description": "'This query looks for sign ins by the Microsoft Entra ID Connect Sync account to Azure where properties about the logon are anomalous.\nThis query uses Microsoft Sentinel's UEBA features to detect these suspicious properties.\nA threat actor may attempt to steal the Sync account credentials and use them to access Azure resources. This alert should be \nreviewed to ensure that the log in came was from a legitimate source.'\n",
"displayName": "Suspicious Sign In by Entra ID Connect Sync Account",
"enabled": true,
"entityMappings": [
{
"entityType": "Account",
"fieldMappings": [
{
"columnName": "UserPrincipalName",
"identifier": "FullName"
},
{
"columnName": "Name",
"identifier": "Name"
},
{
"columnName": "UPNSuffix",
"identifier": "UPNSuffix"
}
]
},
{
"entityType": "IP",
"fieldMappings": [
{
"columnName": "SourceIPAddress",
"identifier": "Address"
}
]
},
{
"entityType": "Host",
"fieldMappings": [
{
"columnName": "DestinationDevice",
"identifier": "HostName"
}
]
}
],
"OriginalUri": "https://github.com/Azure/Azure-Sentinel/blob/master/Detections/BehaviorAnalytics/SuspiciousSigninByAADConnectAccount.yaml",
"query": "BehaviorAnalytics\n// User modification is expected from this account so focus on logons\n| where ActivityType =~ \"LogOn\"\n| where UserName startswith \"Sync_\" and UsersInsights.AccountDisplayName =~ \"On-Premises Directory Synchronization Service Account\"\n// Filter out this expected activity\n| where ActivityInsights.App !~ \"Microsoft Azure Active Directory Connect\"\n| where InvestigationPriority > 0\n| extend Name = split(UserPrincipalName, \"@\")[0], UPNSuffix = split(UserPrincipalName, \"@\")[1]\n",
"queryFrequency": "PT1H",
"queryPeriod": "PT1H",
"severity": "Medium",
"status": "Available",
"subTechniques": [
"T1078.004"
],
"suppressionDuration": "PT1H",
"suppressionEnabled": false,
"tactics": [
"InitialAccess"
],
"techniques": [
"T1078"
],
"templateVersion": "1.0.3",
"triggerOperator": "GreaterThan",
"triggerThreshold": 0
},
"type": "Microsoft.OperationalInsights/workspaces/providers/alertRules"
}
]
}