User Account Created Using Incorrect Naming Format
Id | ee55dc85-d2da-48c1-a6c0-3eaee62a8d56 |
Rulename | User Account Created Using Incorrect Naming Format |
Description | This query looks for accounts being created where the name does not match a defined pattern. Attackers may attempt to add accounts as a means of establishing persistant access to an environment, looking for anomalies in created accounts may help identify illegitimately created accounts. Created accounts should be investigated to ensure they were legitimated created. The user_regex field in the query needs to be populated with the expected pattern for the environment before deployment. Ref: https://docs.microsoft.com/azure/active-directory/fundamentals/security-operations-user-accounts#accounts-not-following-naming-policies |
Severity | Low |
Tactics | Persistence |
Techniques | T1136.003 |
Required data connectors | AzureActiveDirectory |
Kind | Scheduled |
Query frequency | 1d |
Query period | 1d |
Trigger threshold | 0 |
Trigger operator | gt |
Source Uri | https://github.com/Azure/Azure-Sentinel/blob/master/Detections/AuditLogs/UserAccountCreatedUsingIncorrectNamingFormat.yaml |
Version | 1.1.0 |
Arm template | ee55dc85-d2da-48c1-a6c0-3eaee62a8d56.json |
// Add the environments expected username format regex below before deploying
let user_regex = "";
AuditLogs
| where OperationName =~ "Add user"
| where Result =~ "success"
| extend userAgent = tostring(AdditionalDetails[0].value)
| extend InitiatingAppName = tostring(InitiatedBy.app.displayName)
| extend InitiatingAppServicePrincipalId = tostring(InitiatedBy.app.servicePrincipalId)
| extend InitiatingUserPrincipalName = tostring(InitiatedBy.user.userPrincipalName)
| extend InitiatingAadUserId = tostring(InitiatedBy.user.id)
| extend InitiatingIPAddress = tostring(InitiatedBy.user.ipAddress)
| extend InitiatedBy = tostring(iff(isnotempty(InitiatingUserPrincipalName),InitiatingUserPrincipalName, InitiatingAppName))
| extend AddedUser = tostring(TargetResources[0].userPrincipalName)
| where AddedUser matches regex user_regex
| extend InitiatingAccountName = tostring(split(InitiatingUserPrincipalName, "@")[0]), InitiatingAccountUPNSuffix = tostring(split(InitiatingUserPrincipalName, "@")[1])
| extend TargetAccountName = tostring(split(AddedUser, "@")[0]), TargetAccountUPNSuffix = tostring(split(AddedUser, "@")[1])
triggerOperator: gt
queryFrequency: 1d
description: |
'This query looks for accounts being created where the name does not match a defined pattern.
Attackers may attempt to add accounts as a means of establishing persistant access to an environment, looking for anomalies in created accounts may help identify illegitimately created accounts.
Created accounts should be investigated to ensure they were legitimated created.
The user_regex field in the query needs to be populated with the expected pattern for the environment before deployment.
Ref: https://docs.microsoft.com/azure/active-directory/fundamentals/security-operations-user-accounts#accounts-not-following-naming-policies'
version: 1.1.0
kind: Scheduled
triggerThreshold: 0
requiredDataConnectors:
- connectorId: AzureActiveDirectory
dataTypes:
- AuditLogs
queryPeriod: 1d
name: User Account Created Using Incorrect Naming Format
OriginalUri: https://github.com/Azure/Azure-Sentinel/blob/master/Detections/AuditLogs/UserAccountCreatedUsingIncorrectNamingFormat.yaml
id: ee55dc85-d2da-48c1-a6c0-3eaee62a8d56
tags:
- AADSecOpsGuide
tactics:
- Persistence
metadata:
source:
kind: Community
author:
name: Microsoft Security Research
categories:
domains:
- Security - Others
support:
tier: Community
relevantTechniques:
- T1136.003
severity: Low
entityMappings:
- fieldMappings:
- identifier: Name
columnName: InitiatingAppName
- identifier: AadUserId
columnName: InitiatingAppServicePrincipalId
entityType: Account
- fieldMappings:
- identifier: FullName
columnName: InitiatingUserPrincipalName
- identifier: Name
columnName: InitiatingAccountName
- identifier: UPNSuffix
columnName: InitiatingAccountUPNSuffix
entityType: Account
- fieldMappings:
- identifier: AadUserId
columnName: InitiatingAadUserId
entityType: Account
- fieldMappings:
- identifier: FullName
columnName: AddedUser
- identifier: Name
columnName: TargetAccountName
- identifier: UPNSuffix
columnName: TargetAccountUPNSuffix
entityType: Account
- fieldMappings:
- identifier: Address
columnName: InitiatingIPAddress
entityType: IP
query: |
// Add the environments expected username format regex below before deploying
let user_regex = "";
AuditLogs
| where OperationName =~ "Add user"
| where Result =~ "success"
| extend userAgent = tostring(AdditionalDetails[0].value)
| extend InitiatingAppName = tostring(InitiatedBy.app.displayName)
| extend InitiatingAppServicePrincipalId = tostring(InitiatedBy.app.servicePrincipalId)
| extend InitiatingUserPrincipalName = tostring(InitiatedBy.user.userPrincipalName)
| extend InitiatingAadUserId = tostring(InitiatedBy.user.id)
| extend InitiatingIPAddress = tostring(InitiatedBy.user.ipAddress)
| extend InitiatedBy = tostring(iff(isnotempty(InitiatingUserPrincipalName),InitiatingUserPrincipalName, InitiatingAppName))
| extend AddedUser = tostring(TargetResources[0].userPrincipalName)
| where AddedUser matches regex user_regex
| extend InitiatingAccountName = tostring(split(InitiatingUserPrincipalName, "@")[0]), InitiatingAccountUPNSuffix = tostring(split(InitiatingUserPrincipalName, "@")[1])
| extend TargetAccountName = tostring(split(AddedUser, "@")[0]), TargetAccountUPNSuffix = tostring(split(AddedUser, "@")[1])
{
"$schema": "https://schema.management.azure.com/schemas/2019-04-01/deploymentTemplate.json#",
"contentVersion": "1.0.0.0",
"parameters": {
"workspace": {
"type": "String"
}
},
"resources": [
{
"apiVersion": "2023-02-01-preview",
"id": "[concat(resourceId('Microsoft.OperationalInsights/workspaces/providers', parameters('workspace'), 'Microsoft.SecurityInsights'),'/alertRules/ee55dc85-d2da-48c1-a6c0-3eaee62a8d56')]",
"kind": "Scheduled",
"name": "[concat(parameters('workspace'),'/Microsoft.SecurityInsights/ee55dc85-d2da-48c1-a6c0-3eaee62a8d56')]",
"properties": {
"alertRuleTemplateName": "ee55dc85-d2da-48c1-a6c0-3eaee62a8d56",
"customDetails": null,
"description": "'This query looks for accounts being created where the name does not match a defined pattern.\n Attackers may attempt to add accounts as a means of establishing persistant access to an environment, looking for anomalies in created accounts may help identify illegitimately created accounts.\n Created accounts should be investigated to ensure they were legitimated created.\n The user_regex field in the query needs to be populated with the expected pattern for the environment before deployment.\n Ref: https://docs.microsoft.com/azure/active-directory/fundamentals/security-operations-user-accounts#accounts-not-following-naming-policies'\n",
"displayName": "User Account Created Using Incorrect Naming Format",
"enabled": true,
"entityMappings": [
{
"entityType": "Account",
"fieldMappings": [
{
"columnName": "InitiatingAppName",
"identifier": "Name"
},
{
"columnName": "InitiatingAppServicePrincipalId",
"identifier": "AadUserId"
}
]
},
{
"entityType": "Account",
"fieldMappings": [
{
"columnName": "InitiatingUserPrincipalName",
"identifier": "FullName"
},
{
"columnName": "InitiatingAccountName",
"identifier": "Name"
},
{
"columnName": "InitiatingAccountUPNSuffix",
"identifier": "UPNSuffix"
}
]
},
{
"entityType": "Account",
"fieldMappings": [
{
"columnName": "InitiatingAadUserId",
"identifier": "AadUserId"
}
]
},
{
"entityType": "Account",
"fieldMappings": [
{
"columnName": "AddedUser",
"identifier": "FullName"
},
{
"columnName": "TargetAccountName",
"identifier": "Name"
},
{
"columnName": "TargetAccountUPNSuffix",
"identifier": "UPNSuffix"
}
]
},
{
"entityType": "IP",
"fieldMappings": [
{
"columnName": "InitiatingIPAddress",
"identifier": "Address"
}
]
}
],
"OriginalUri": "https://github.com/Azure/Azure-Sentinel/blob/master/Detections/AuditLogs/UserAccountCreatedUsingIncorrectNamingFormat.yaml",
"query": "// Add the environments expected username format regex below before deploying\nlet user_regex = \"\";\nAuditLogs\n| where OperationName =~ \"Add user\"\n| where Result =~ \"success\"\n| extend userAgent = tostring(AdditionalDetails[0].value)\n| extend InitiatingAppName = tostring(InitiatedBy.app.displayName)\n| extend InitiatingAppServicePrincipalId = tostring(InitiatedBy.app.servicePrincipalId)\n| extend InitiatingUserPrincipalName = tostring(InitiatedBy.user.userPrincipalName)\n| extend InitiatingAadUserId = tostring(InitiatedBy.user.id)\n| extend InitiatingIPAddress = tostring(InitiatedBy.user.ipAddress)\n| extend InitiatedBy = tostring(iff(isnotempty(InitiatingUserPrincipalName),InitiatingUserPrincipalName, InitiatingAppName))\n| extend AddedUser = tostring(TargetResources[0].userPrincipalName)\n| where AddedUser matches regex user_regex\n| extend InitiatingAccountName = tostring(split(InitiatingUserPrincipalName, \"@\")[0]), InitiatingAccountUPNSuffix = tostring(split(InitiatingUserPrincipalName, \"@\")[1])\n| extend TargetAccountName = tostring(split(AddedUser, \"@\")[0]), TargetAccountUPNSuffix = tostring(split(AddedUser, \"@\")[1])\n",
"queryFrequency": "P1D",
"queryPeriod": "P1D",
"severity": "Low",
"suppressionDuration": "PT1H",
"suppressionEnabled": false,
"tactics": [
"Persistence"
],
"tags": [
"AADSecOpsGuide"
],
"techniques": [
"T1136"
],
"templateVersion": "1.1.0",
"triggerOperator": "GreaterThan",
"triggerThreshold": 0
},
"type": "Microsoft.OperationalInsights/workspaces/providers/alertRules"
}
]
}