Account added and removed from privileged groups
| Id | 7efc75ce-e2a4-400f-a8b1-283d3b0f2c60 |
| Rulename | Account added and removed from privileged groups |
| Description | Identifies accounts that are added to a privileged group and then quickly removed, which could be a sign of compromise. |
| Severity | Low |
| Tactics | Persistence PrivilegeEscalation |
| Techniques | T1098 T1078 |
| Required data connectors | SecurityEvents WindowsForwardedEvents WindowsSecurityEvents |
| 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/SecurityEvent/UserAccountAdd-Removed.yaml |
| Version | 1.1.5 |
| Arm template | 7efc75ce-e2a4-400f-a8b1-283d3b0f2c60.json |
let WellKnownLocalSID = "S-1-5-32-5[0-9][0-9]$";
let WellKnownGroupSID = "S-1-5-21-[0-9]*-[0-9]*-[0-9]*-5[0-9][0-9]$|S-1-5-21-[0-9]*-[0-9]*-[0-9]*-1102$|S-1-5-21-[0-9]*-[0-9]*-[0-9]*-1103$|S-1-5-21-[0-9]*-[0-9]*-[0-9]*-498$|S-1-5-21-[0-9]*-[0-9]*-[0-9]*-1000$";
let AC_Add =
(union isfuzzy=true
(SecurityEvent
// Event ID related to member addition.
| where EventID in (4728, 4732,4756)
| where TargetSid matches regex WellKnownLocalSID or TargetSid matches regex WellKnownGroupSID
| parse EventData with * '"MemberName">' * '=' AccountAdded ",OU" *
| where isnotempty(AccountAdded)
| extend GroupAddedTo = TargetUserName, AddingAccount = Account
| extend AccountAdded_GroupAddedTo_AddingAccount = strcat(AccountAdded, "||", GroupAddedTo, "||", AddingAccount )
| project AccountAdded_GroupAddedTo_AddingAccount, AccountAddedTime = TimeGenerated
),
(WindowsEvent
// Event ID related to member addition.
| where EventID in (4728, 4732,4756)
| extend TargetSid = tostring(EventData.TargetSid)
| where TargetSid matches regex WellKnownLocalSID or TargetSid matches regex WellKnownGroupSID
| parse EventData.MemberName with * '"MemberName">' * '=' AccountAdded ",OU" *
| where isnotempty(AccountAdded)
| extend TargetUserName = tostring(EventData.TargetUserName)
| extend AddingAccount = strcat(tostring(EventData.SubjectDomainName),"\\", tostring(EventData.SubjectUserName))
| extend GroupAddedTo = TargetUserName
| extend AccountAdded_GroupAddedTo_AddingAccount = strcat(AccountAdded, "||", GroupAddedTo, "||", AddingAccount )
| project AccountAdded_GroupAddedTo_AddingAccount, AccountAddedTime = TimeGenerated
)
);
let AC_Remove =
( union isfuzzy=true
(SecurityEvent
// Event IDs related to member removal.
| where EventID in (4729,4733,4757)
| where TargetSid matches regex WellKnownLocalSID or TargetSid matches regex WellKnownGroupSID
| parse EventData with * '"MemberName">' * '=' AccountRemoved ",OU" *
| where isnotempty(AccountRemoved)
| extend GroupRemovedFrom = TargetUserName, RemovingAccount = Account
| extend AccountRemoved_GroupRemovedFrom_RemovingAccount = strcat(AccountRemoved, "||", GroupRemovedFrom, "||", RemovingAccount)
| project AccountRemoved_GroupRemovedFrom_RemovingAccount, AccountRemovedTime = TimeGenerated, Computer, AccountRemoved = tolower(AccountRemoved),
RemovingAccount, RemovingAccountLogonId = SubjectLogonId, GroupRemovedFrom = TargetUserName, TargetDomainName
),
(WindowsEvent
// Event IDs related to member removal.
| where EventID in (4729,4733,4757)
| extend TargetSid = tostring(EventData.TargetSid)
| where TargetSid matches regex WellKnownLocalSID or TargetSid matches regex WellKnownGroupSID
| parse EventData.MemberName with * '"MemberName">' * '=' AccountRemoved ",OU" *
| where isnotempty(AccountRemoved)
| extend TargetUserName = tostring(EventData.TargetUserName)
| extend RemovingAccount = strcat(tostring(EventData.SubjectDomainName),"\\", tostring(EventData.SubjectUserName))
| extend GroupRemovedFrom = TargetUserName
| extend AccountRemoved_GroupRemovedFrom_RemovingAccount = strcat(AccountRemoved, "||", GroupRemovedFrom, "||", RemovingAccount)
| extend RemovedAccountLogonId= tostring(EventData.SubjectLogonId)
| extend TargetDomainName = tostring(EventData.TargetDomainName)
| project AccountRemoved_GroupRemovedFrom_RemovingAccount, AccountRemovedTime = TimeGenerated, Computer, AccountRemoved = tolower(AccountRemoved),
RemovingAccount, RemovedAccountLogonId, GroupRemovedFrom = TargetUserName, TargetDomainName
));
AC_Add
| join kind = inner AC_Remove
on $left.AccountAdded_GroupAddedTo_AddingAccount == $right.AccountRemoved_GroupRemovedFrom_RemovingAccount
| extend DurationinSecondAfter_Removed = datetime_diff ('second', AccountRemovedTime, AccountAddedTime)
| where DurationinSecondAfter_Removed > 0
| extend HostName = tostring(split(Computer, ".")[0]), DomainIndex = toint(indexof(Computer, '.'))
| extend HostNameDomain = iff(DomainIndex != -1, substring(Computer, DomainIndex + 1), Computer)
| extend RemovedAccountName = tostring(split(AccountRemoved, @"\")[1]), RemovedAccountNTDomain = tostring(split(AccountRemoved, @"\")[0])
| extend RemovingAccountName = tostring(split(RemovingAccount, @"\")[1]), RemovingAccountNTDomain = tostring(split(RemovingAccount, @"\")[0])
| project-away DomainIndex
relevantTechniques:
- T1098
- T1078
name: Account added and removed from privileged groups
requiredDataConnectors:
- dataTypes:
- SecurityEvent
connectorId: SecurityEvents
- dataTypes:
- SecurityEvent
connectorId: WindowsSecurityEvents
- dataTypes:
- WindowsEvent
connectorId: WindowsForwardedEvents
entityMappings:
- fieldMappings:
- identifier: FullName
columnName: AccountRemoved
- identifier: Name
columnName: RemovedAccountName
- identifier: NTDomain
columnName: RemovedAccountNTDomain
entityType: Account
- fieldMappings:
- identifier: FullName
columnName: RemovingAccount
- identifier: Name
columnName: RemovingAccountName
- identifier: NTDomain
columnName: RemovingAccountNTDomain
entityType: Account
- fieldMappings:
- identifier: FullName
columnName: Computer
- identifier: HostName
columnName: HostName
- identifier: NTDomain
columnName: HostNameDomain
entityType: Host
triggerThreshold: 0
id: 7efc75ce-e2a4-400f-a8b1-283d3b0f2c60
tactics:
- Persistence
- PrivilegeEscalation
version: 1.1.5
OriginalUri: https://github.com/Azure/Azure-Sentinel/blob/master/Detections/SecurityEvent/UserAccountAdd-Removed.yaml
queryPeriod: 1d
kind: Scheduled
metadata:
categories:
domains:
- Security - Others
- Identity
author:
name: Microsoft Security Research
support:
tier: Community
source:
kind: Community
queryFrequency: 1d
severity: Low
description: |
'Identifies accounts that are added to a privileged group and then quickly removed, which could be a sign of compromise.'
query: |
let WellKnownLocalSID = "S-1-5-32-5[0-9][0-9]$";
let WellKnownGroupSID = "S-1-5-21-[0-9]*-[0-9]*-[0-9]*-5[0-9][0-9]$|S-1-5-21-[0-9]*-[0-9]*-[0-9]*-1102$|S-1-5-21-[0-9]*-[0-9]*-[0-9]*-1103$|S-1-5-21-[0-9]*-[0-9]*-[0-9]*-498$|S-1-5-21-[0-9]*-[0-9]*-[0-9]*-1000$";
let AC_Add =
(union isfuzzy=true
(SecurityEvent
// Event ID related to member addition.
| where EventID in (4728, 4732,4756)
| where TargetSid matches regex WellKnownLocalSID or TargetSid matches regex WellKnownGroupSID
| parse EventData with * '"MemberName">' * '=' AccountAdded ",OU" *
| where isnotempty(AccountAdded)
| extend GroupAddedTo = TargetUserName, AddingAccount = Account
| extend AccountAdded_GroupAddedTo_AddingAccount = strcat(AccountAdded, "||", GroupAddedTo, "||", AddingAccount )
| project AccountAdded_GroupAddedTo_AddingAccount, AccountAddedTime = TimeGenerated
),
(WindowsEvent
// Event ID related to member addition.
| where EventID in (4728, 4732,4756)
| extend TargetSid = tostring(EventData.TargetSid)
| where TargetSid matches regex WellKnownLocalSID or TargetSid matches regex WellKnownGroupSID
| parse EventData.MemberName with * '"MemberName">' * '=' AccountAdded ",OU" *
| where isnotempty(AccountAdded)
| extend TargetUserName = tostring(EventData.TargetUserName)
| extend AddingAccount = strcat(tostring(EventData.SubjectDomainName),"\\", tostring(EventData.SubjectUserName))
| extend GroupAddedTo = TargetUserName
| extend AccountAdded_GroupAddedTo_AddingAccount = strcat(AccountAdded, "||", GroupAddedTo, "||", AddingAccount )
| project AccountAdded_GroupAddedTo_AddingAccount, AccountAddedTime = TimeGenerated
)
);
let AC_Remove =
( union isfuzzy=true
(SecurityEvent
// Event IDs related to member removal.
| where EventID in (4729,4733,4757)
| where TargetSid matches regex WellKnownLocalSID or TargetSid matches regex WellKnownGroupSID
| parse EventData with * '"MemberName">' * '=' AccountRemoved ",OU" *
| where isnotempty(AccountRemoved)
| extend GroupRemovedFrom = TargetUserName, RemovingAccount = Account
| extend AccountRemoved_GroupRemovedFrom_RemovingAccount = strcat(AccountRemoved, "||", GroupRemovedFrom, "||", RemovingAccount)
| project AccountRemoved_GroupRemovedFrom_RemovingAccount, AccountRemovedTime = TimeGenerated, Computer, AccountRemoved = tolower(AccountRemoved),
RemovingAccount, RemovingAccountLogonId = SubjectLogonId, GroupRemovedFrom = TargetUserName, TargetDomainName
),
(WindowsEvent
// Event IDs related to member removal.
| where EventID in (4729,4733,4757)
| extend TargetSid = tostring(EventData.TargetSid)
| where TargetSid matches regex WellKnownLocalSID or TargetSid matches regex WellKnownGroupSID
| parse EventData.MemberName with * '"MemberName">' * '=' AccountRemoved ",OU" *
| where isnotempty(AccountRemoved)
| extend TargetUserName = tostring(EventData.TargetUserName)
| extend RemovingAccount = strcat(tostring(EventData.SubjectDomainName),"\\", tostring(EventData.SubjectUserName))
| extend GroupRemovedFrom = TargetUserName
| extend AccountRemoved_GroupRemovedFrom_RemovingAccount = strcat(AccountRemoved, "||", GroupRemovedFrom, "||", RemovingAccount)
| extend RemovedAccountLogonId= tostring(EventData.SubjectLogonId)
| extend TargetDomainName = tostring(EventData.TargetDomainName)
| project AccountRemoved_GroupRemovedFrom_RemovingAccount, AccountRemovedTime = TimeGenerated, Computer, AccountRemoved = tolower(AccountRemoved),
RemovingAccount, RemovedAccountLogonId, GroupRemovedFrom = TargetUserName, TargetDomainName
));
AC_Add
| join kind = inner AC_Remove
on $left.AccountAdded_GroupAddedTo_AddingAccount == $right.AccountRemoved_GroupRemovedFrom_RemovingAccount
| extend DurationinSecondAfter_Removed = datetime_diff ('second', AccountRemovedTime, AccountAddedTime)
| where DurationinSecondAfter_Removed > 0
| extend HostName = tostring(split(Computer, ".")[0]), DomainIndex = toint(indexof(Computer, '.'))
| extend HostNameDomain = iff(DomainIndex != -1, substring(Computer, DomainIndex + 1), Computer)
| extend RemovedAccountName = tostring(split(AccountRemoved, @"\")[1]), RemovedAccountNTDomain = tostring(split(AccountRemoved, @"\")[0])
| extend RemovingAccountName = tostring(split(RemovingAccount, @"\")[1]), RemovingAccountNTDomain = tostring(split(RemovingAccount, @"\")[0])
| project-away DomainIndex
triggerOperator: gt
{
"$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/7efc75ce-e2a4-400f-a8b1-283d3b0f2c60')]",
"kind": "Scheduled",
"name": "[concat(parameters('workspace'),'/Microsoft.SecurityInsights/7efc75ce-e2a4-400f-a8b1-283d3b0f2c60')]",
"properties": {
"alertRuleTemplateName": "7efc75ce-e2a4-400f-a8b1-283d3b0f2c60",
"customDetails": null,
"description": "'Identifies accounts that are added to a privileged group and then quickly removed, which could be a sign of compromise.'\n",
"displayName": "Account added and removed from privileged groups",
"enabled": true,
"entityMappings": [
{
"entityType": "Account",
"fieldMappings": [
{
"columnName": "AccountRemoved",
"identifier": "FullName"
},
{
"columnName": "RemovedAccountName",
"identifier": "Name"
},
{
"columnName": "RemovedAccountNTDomain",
"identifier": "NTDomain"
}
]
},
{
"entityType": "Account",
"fieldMappings": [
{
"columnName": "RemovingAccount",
"identifier": "FullName"
},
{
"columnName": "RemovingAccountName",
"identifier": "Name"
},
{
"columnName": "RemovingAccountNTDomain",
"identifier": "NTDomain"
}
]
},
{
"entityType": "Host",
"fieldMappings": [
{
"columnName": "Computer",
"identifier": "FullName"
},
{
"columnName": "HostName",
"identifier": "HostName"
},
{
"columnName": "HostNameDomain",
"identifier": "NTDomain"
}
]
}
],
"OriginalUri": "https://github.com/Azure/Azure-Sentinel/blob/master/Detections/SecurityEvent/UserAccountAdd-Removed.yaml",
"query": "let WellKnownLocalSID = \"S-1-5-32-5[0-9][0-9]$\";\nlet WellKnownGroupSID = \"S-1-5-21-[0-9]*-[0-9]*-[0-9]*-5[0-9][0-9]$|S-1-5-21-[0-9]*-[0-9]*-[0-9]*-1102$|S-1-5-21-[0-9]*-[0-9]*-[0-9]*-1103$|S-1-5-21-[0-9]*-[0-9]*-[0-9]*-498$|S-1-5-21-[0-9]*-[0-9]*-[0-9]*-1000$\";\nlet AC_Add =\n(union isfuzzy=true\n(SecurityEvent\n// Event ID related to member addition.\n| where EventID in (4728, 4732,4756)\n| where TargetSid matches regex WellKnownLocalSID or TargetSid matches regex WellKnownGroupSID\n| parse EventData with * '\"MemberName\">' * '=' AccountAdded \",OU\" *\n| where isnotempty(AccountAdded)\n| extend GroupAddedTo = TargetUserName, AddingAccount = Account\n| extend AccountAdded_GroupAddedTo_AddingAccount = strcat(AccountAdded, \"||\", GroupAddedTo, \"||\", AddingAccount )\n| project AccountAdded_GroupAddedTo_AddingAccount, AccountAddedTime = TimeGenerated\n),\n(WindowsEvent\n// Event ID related to member addition.\n| where EventID in (4728, 4732,4756)\n| extend TargetSid = tostring(EventData.TargetSid)\n| where TargetSid matches regex WellKnownLocalSID or TargetSid matches regex WellKnownGroupSID\n| parse EventData.MemberName with * '\"MemberName\">' * '=' AccountAdded \",OU\" *\n| where isnotempty(AccountAdded)\n| extend TargetUserName = tostring(EventData.TargetUserName)\n| extend AddingAccount = strcat(tostring(EventData.SubjectDomainName),\"\\\\\", tostring(EventData.SubjectUserName))\n| extend GroupAddedTo = TargetUserName\n| extend AccountAdded_GroupAddedTo_AddingAccount = strcat(AccountAdded, \"||\", GroupAddedTo, \"||\", AddingAccount )\n| project AccountAdded_GroupAddedTo_AddingAccount, AccountAddedTime = TimeGenerated\n)\n);\nlet AC_Remove =\n( union isfuzzy=true\n(SecurityEvent\n// Event IDs related to member removal.\n| where EventID in (4729,4733,4757)\n| where TargetSid matches regex WellKnownLocalSID or TargetSid matches regex WellKnownGroupSID\n| parse EventData with * '\"MemberName\">' * '=' AccountRemoved \",OU\" *\n| where isnotempty(AccountRemoved)\n| extend GroupRemovedFrom = TargetUserName, RemovingAccount = Account\n| extend AccountRemoved_GroupRemovedFrom_RemovingAccount = strcat(AccountRemoved, \"||\", GroupRemovedFrom, \"||\", RemovingAccount)\n| project AccountRemoved_GroupRemovedFrom_RemovingAccount, AccountRemovedTime = TimeGenerated, Computer, AccountRemoved = tolower(AccountRemoved),\nRemovingAccount, RemovingAccountLogonId = SubjectLogonId, GroupRemovedFrom = TargetUserName, TargetDomainName\n),\n(WindowsEvent\n// Event IDs related to member removal.\n| where EventID in (4729,4733,4757)\n| extend TargetSid = tostring(EventData.TargetSid)\n| where TargetSid matches regex WellKnownLocalSID or TargetSid matches regex WellKnownGroupSID\n| parse EventData.MemberName with * '\"MemberName\">' * '=' AccountRemoved \",OU\" *\n| where isnotempty(AccountRemoved)\n| extend TargetUserName = tostring(EventData.TargetUserName)\n| extend RemovingAccount = strcat(tostring(EventData.SubjectDomainName),\"\\\\\", tostring(EventData.SubjectUserName))\n| extend GroupRemovedFrom = TargetUserName\n| extend AccountRemoved_GroupRemovedFrom_RemovingAccount = strcat(AccountRemoved, \"||\", GroupRemovedFrom, \"||\", RemovingAccount)\n| extend RemovedAccountLogonId= tostring(EventData.SubjectLogonId)\n| extend TargetDomainName = tostring(EventData.TargetDomainName)\n| project AccountRemoved_GroupRemovedFrom_RemovingAccount, AccountRemovedTime = TimeGenerated, Computer, AccountRemoved = tolower(AccountRemoved),\nRemovingAccount, RemovedAccountLogonId, GroupRemovedFrom = TargetUserName, TargetDomainName\n));\nAC_Add\n| join kind = inner AC_Remove \non $left.AccountAdded_GroupAddedTo_AddingAccount == $right.AccountRemoved_GroupRemovedFrom_RemovingAccount\n| extend DurationinSecondAfter_Removed = datetime_diff ('second', AccountRemovedTime, AccountAddedTime)\n| where DurationinSecondAfter_Removed > 0\n| extend HostName = tostring(split(Computer, \".\")[0]), DomainIndex = toint(indexof(Computer, '.'))\n| extend HostNameDomain = iff(DomainIndex != -1, substring(Computer, DomainIndex + 1), Computer)\n| extend RemovedAccountName = tostring(split(AccountRemoved, @\"\\\")[1]), RemovedAccountNTDomain = tostring(split(AccountRemoved, @\"\\\")[0])\n| extend RemovingAccountName = tostring(split(RemovingAccount, @\"\\\")[1]), RemovingAccountNTDomain = tostring(split(RemovingAccount, @\"\\\")[0])\n| project-away DomainIndex\n",
"queryFrequency": "P1D",
"queryPeriod": "P1D",
"severity": "Low",
"subTechniques": [],
"suppressionDuration": "PT1H",
"suppressionEnabled": false,
"tactics": [
"Persistence",
"PrivilegeEscalation"
],
"techniques": [
"T1078",
"T1098"
],
"templateVersion": "1.1.5",
"triggerOperator": "GreaterThan",
"triggerThreshold": 0
},
"type": "Microsoft.OperationalInsights/workspaces/providers/alertRules"
}
]
}