User account created and deleted within 10 mins

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Id	4b93c5af-d20b-4236-b696-a28b8c51407f
Rulename	User account created and deleted within 10 mins
Description	Identifies when a user account is created and then deleted within 10 minutes. This can be an indication of compromise and an adversary attempting to hide in the noise.
Severity	Medium
Tactics	Persistence PrivilegeEscalation
Techniques	T1098 T1078
Required data connectors	SecurityEvents WindowsForwardedEvents WindowsSecurityEvents
Kind	Scheduled
Query frequency	1d
Query period	25h
Trigger threshold	0
Trigger operator	gt
Source Uri	https://github.com/Azure/Azure-Sentinel/blob/master/Detections/SecurityEvent/UserAccountCreatedDeleted_10m.yaml
Version	1.2.2
Arm template	4b93c5af-d20b-4236-b696-a28b8c51407f.json

KQL

let timeframe = 1d;
let spanoftime = 10m;
let threshold = 0;
(union isfuzzy=true
    (SecurityEvent
    | where TimeGenerated > ago(timeframe+spanoftime)
    // A user account was created
    | where EventID == 4720
    | where AccountType =~ "User"
    | project creationTime = TimeGenerated, CreateEventID = EventID, CreateActivity = Activity, Computer = toupper(Computer), 
    TargetAccount = tolower(TargetAccount), TargetUserName, TargetDomainName, TargetSid, 
    AccountUsedToCreate = SubjectAccount, CreatedBySubjectUserName = SubjectUserName, CreatedBySubjectDomainName = SubjectDomainName, SIDofAccountUsedToCreate = SubjectUserSid, UserPrincipalName
    ),
    (
    WindowsEvent
    | where TimeGenerated > ago(timeframe+spanoftime)
    // A user account was created
    | where EventID == 4720
    | extend SubjectUserSid = tostring(EventData.SubjectUserSid)
    | extend AccountType=case(EventData.SubjectUserName endswith "$" or SubjectUserSid in ("S-1-5-18", "S-1-5-19", "S-1-5-20"), "Machine", isempty(SubjectUserSid), "", "User")
    | where AccountType =~ "User"
    | extend SubjectAccount = strcat(tostring(EventData.SubjectDomainName),"\\", tostring(EventData.SubjectUserName))
    | extend SubjectDomainName = tostring(EventData.SubjectDomainName), SubjectUserName = tostring(EventData.SubjectUserName)
    | extend TargetAccount = strcat(EventData.TargetDomainName,"\\", EventData.TargetUserName)
    | extend TargetSid = tostring(EventData.TargetSid)
    | extend UserPrincipalName = tostring(EventData.UserPrincipalName)
    | extend Activity = "4720 - A user account was created."
    | extend TargetUserName = tostring(EventData.TargetUserName), TargetDomainName = tostring(EventData.TargetDomainName) 
    | project creationTime = TimeGenerated, CreateEventID = EventID, CreateActivity = Activity, Computer = toupper(Computer), 
    TargetAccount = tolower(TargetAccount), TargetUserName, TargetDomainName, TargetSid, 
    AccountUsedToCreate = SubjectAccount, CreatedBySubjectUserName = SubjectUserName, CreatedBySubjectDomainName = SubjectDomainName, SIDofAccountUsedToCreate = SubjectUserSid, UserPrincipalName
    )
  )
| join kind = inner 
(
  (union isfuzzy=true
    (SecurityEvent
    | where TimeGenerated > ago(timeframe)
    // A user account was deleted
    | where EventID == 4726
    | where AccountType == "User"
    | project deletionTime = TimeGenerated, DeleteEventID = EventID, DeleteActivity = Activity, Computer = toupper(Computer), 
    TargetAccount = tolower(TargetAccount), TargetUserName, TargetDomainName, TargetSid, 
    AccountUsedToDelete = SubjectAccount, DeletedBySubjectUserName = SubjectUserName, DeletedBySubjectDomainName = SubjectDomainName, SIDofAccountUsedToDelete = SubjectUserSid, UserPrincipalName
    ),
    (WindowsEvent
    | where TimeGenerated > ago(timeframe)
    // A user account was deleted
    | where EventID == 4726
    | extend SubjectUserSid = tostring(EventData.SubjectUserSid)
    | extend SubjectAccount = strcat(tostring(EventData.SubjectDomainName),"\\", tostring(EventData.SubjectUserName))
    | extend AccountType=case(SubjectAccount endswith "$" or SubjectUserSid in ("S-1-5-18", "S-1-5-19", "S-1-5-20"), "Machine", isempty(SubjectUserSid), "", "User")
    | where AccountType == "User"
    | extend SubjectDomainName = tostring(EventData.SubjectDomainName), SubjectUserName = tostring(EventData.SubjectUserName)
    | extend TargetSid = tostring(EventData.TargetSid)
    | extend UserPrincipalName = tostring(EventData.UserPrincipalName)
    | extend Activity = "4726 - A user account was deleted."
    | extend TargetUserName = tostring(EventData.TargetUserName), TargetDomainName = tostring(EventData.TargetDomainName) 
    | extend TargetAccount = strcat(EventData.TargetDomainName,"\\", EventData.TargetUserName)
    | project deletionTime = TimeGenerated, DeleteEventID = EventID, DeleteActivity = Activity, Computer = toupper(Computer), 
    TargetAccount = tolower(TargetAccount), TargetUserName, TargetDomainName, TargetSid, 
    AccountUsedToDelete = SubjectAccount, DeletedBySubjectUserName = SubjectUserName, DeletedBySubjectDomainName = SubjectDomainName, SIDofAccountUsedToDelete = SubjectUserSid, UserPrincipalName
    )
  )
) on Computer, TargetAccount
| where deletionTime - creationTime < spanoftime
| extend TimeDelta = deletionTime - creationTime
| where tolong(TimeDelta) >= threshold
| project TimeDelta, creationTime, CreateEventID, CreateActivity, Computer, TargetAccount, TargetSid, UserPrincipalName, AccountUsedToCreate, SIDofAccountUsedToCreate,
deletionTime, DeleteEventID, DeleteActivity, AccountUsedToDelete, SIDofAccountUsedToDelete, TargetUserName, TargetDomainName, 
CreatedBySubjectUserName, CreatedBySubjectDomainName, DeletedBySubjectUserName, DeletedBySubjectDomainName
| extend HostName = tostring(split(Computer, ".")[0]), DomainIndex = toint(indexof(Computer, '.'))
| extend HostNameDomain = iff(DomainIndex != -1, substring(Computer, DomainIndex + 1), Computer)
| project-away DomainIndex

YAML

tactics:
- Persistence
- PrivilegeEscalation
query: |
  let timeframe = 1d;
  let spanoftime = 10m;
  let threshold = 0;
  (union isfuzzy=true
      (SecurityEvent
      | where TimeGenerated > ago(timeframe+spanoftime)
      // A user account was created
      | where EventID == 4720
      | where AccountType =~ "User"
      | project creationTime = TimeGenerated, CreateEventID = EventID, CreateActivity = Activity, Computer = toupper(Computer), 
      TargetAccount = tolower(TargetAccount), TargetUserName, TargetDomainName, TargetSid, 
      AccountUsedToCreate = SubjectAccount, CreatedBySubjectUserName = SubjectUserName, CreatedBySubjectDomainName = SubjectDomainName, SIDofAccountUsedToCreate = SubjectUserSid, UserPrincipalName
      ),
      (
      WindowsEvent
      | where TimeGenerated > ago(timeframe+spanoftime)
      // A user account was created
      | where EventID == 4720
      | extend SubjectUserSid = tostring(EventData.SubjectUserSid)
      | extend AccountType=case(EventData.SubjectUserName endswith "$" or SubjectUserSid in ("S-1-5-18", "S-1-5-19", "S-1-5-20"), "Machine", isempty(SubjectUserSid), "", "User")
      | where AccountType =~ "User"
      | extend SubjectAccount = strcat(tostring(EventData.SubjectDomainName),"\\", tostring(EventData.SubjectUserName))
      | extend SubjectDomainName = tostring(EventData.SubjectDomainName), SubjectUserName = tostring(EventData.SubjectUserName)
      | extend TargetAccount = strcat(EventData.TargetDomainName,"\\", EventData.TargetUserName)
      | extend TargetSid = tostring(EventData.TargetSid)
      | extend UserPrincipalName = tostring(EventData.UserPrincipalName)
      | extend Activity = "4720 - A user account was created."
      | extend TargetUserName = tostring(EventData.TargetUserName), TargetDomainName = tostring(EventData.TargetDomainName) 
      | project creationTime = TimeGenerated, CreateEventID = EventID, CreateActivity = Activity, Computer = toupper(Computer), 
      TargetAccount = tolower(TargetAccount), TargetUserName, TargetDomainName, TargetSid, 
      AccountUsedToCreate = SubjectAccount, CreatedBySubjectUserName = SubjectUserName, CreatedBySubjectDomainName = SubjectDomainName, SIDofAccountUsedToCreate = SubjectUserSid, UserPrincipalName
      )
    )
  | join kind = inner 
  (
    (union isfuzzy=true
      (SecurityEvent
      | where TimeGenerated > ago(timeframe)
      // A user account was deleted
      | where EventID == 4726
      | where AccountType == "User"
      | project deletionTime = TimeGenerated, DeleteEventID = EventID, DeleteActivity = Activity, Computer = toupper(Computer), 
      TargetAccount = tolower(TargetAccount), TargetUserName, TargetDomainName, TargetSid, 
      AccountUsedToDelete = SubjectAccount, DeletedBySubjectUserName = SubjectUserName, DeletedBySubjectDomainName = SubjectDomainName, SIDofAccountUsedToDelete = SubjectUserSid, UserPrincipalName
      ),
      (WindowsEvent
      | where TimeGenerated > ago(timeframe)
      // A user account was deleted
      | where EventID == 4726
      | extend SubjectUserSid = tostring(EventData.SubjectUserSid)
      | extend SubjectAccount = strcat(tostring(EventData.SubjectDomainName),"\\", tostring(EventData.SubjectUserName))
      | extend AccountType=case(SubjectAccount endswith "$" or SubjectUserSid in ("S-1-5-18", "S-1-5-19", "S-1-5-20"), "Machine", isempty(SubjectUserSid), "", "User")
      | where AccountType == "User"
      | extend SubjectDomainName = tostring(EventData.SubjectDomainName), SubjectUserName = tostring(EventData.SubjectUserName)
      | extend TargetSid = tostring(EventData.TargetSid)
      | extend UserPrincipalName = tostring(EventData.UserPrincipalName)
      | extend Activity = "4726 - A user account was deleted."
      | extend TargetUserName = tostring(EventData.TargetUserName), TargetDomainName = tostring(EventData.TargetDomainName) 
      | extend TargetAccount = strcat(EventData.TargetDomainName,"\\", EventData.TargetUserName)
      | project deletionTime = TimeGenerated, DeleteEventID = EventID, DeleteActivity = Activity, Computer = toupper(Computer), 
      TargetAccount = tolower(TargetAccount), TargetUserName, TargetDomainName, TargetSid, 
      AccountUsedToDelete = SubjectAccount, DeletedBySubjectUserName = SubjectUserName, DeletedBySubjectDomainName = SubjectDomainName, SIDofAccountUsedToDelete = SubjectUserSid, UserPrincipalName
      )
    )
  ) on Computer, TargetAccount
  | where deletionTime - creationTime < spanoftime
  | extend TimeDelta = deletionTime - creationTime
  | where tolong(TimeDelta) >= threshold
  | project TimeDelta, creationTime, CreateEventID, CreateActivity, Computer, TargetAccount, TargetSid, UserPrincipalName, AccountUsedToCreate, SIDofAccountUsedToCreate,
  deletionTime, DeleteEventID, DeleteActivity, AccountUsedToDelete, SIDofAccountUsedToDelete, TargetUserName, TargetDomainName, 
  CreatedBySubjectUserName, CreatedBySubjectDomainName, DeletedBySubjectUserName, DeletedBySubjectDomainName
  | extend HostName = tostring(split(Computer, ".")[0]), DomainIndex = toint(indexof(Computer, '.'))
  | extend HostNameDomain = iff(DomainIndex != -1, substring(Computer, DomainIndex + 1), Computer)
  | project-away DomainIndex  
triggerOperator: gt
version: 1.2.2
triggerThreshold: 0
kind: Scheduled
name: User account created and deleted within 10 mins
OriginalUri: https://github.com/Azure/Azure-Sentinel/blob/master/Detections/SecurityEvent/UserAccountCreatedDeleted_10m.yaml
id: 4b93c5af-d20b-4236-b696-a28b8c51407f
queryFrequency: 1d
queryPeriod: 25h
metadata:
  support:
    tier: Community
  source:
    kind: Community
  author:
    name: Microsoft Security Research
  categories:
    domains:
    - Security - Others
    - Identity
requiredDataConnectors:
- dataTypes:
  - SecurityEvent
  connectorId: SecurityEvents
- dataTypes:
  - SecurityEvent
  connectorId: WindowsSecurityEvents
- dataTypes:
  - WindowsEvent
  connectorId: WindowsForwardedEvents
description: |
    'Identifies when a user account is created and then deleted within 10 minutes. This can be an indication of compromise and an adversary attempting to hide in the noise.'
relevantTechniques:
- T1098
- T1078
entityMappings:
- fieldMappings:
  - columnName: AccountUsedToCreate
    identifier: FullName
  - columnName: CreatedBySubjectUserName
    identifier: Name
  - columnName: CreatedBySubjectDomainName
    identifier: NTDomain
  entityType: Account
- fieldMappings:
  - columnName: AccountUsedToDelete
    identifier: FullName
  - columnName: DeletedBySubjectUserName
    identifier: Name
  - columnName: DeletedBySubjectDomainName
    identifier: NTDomain
  entityType: Account
- fieldMappings:
  - columnName: TargetAccount
    identifier: FullName
  - columnName: TargetUserName
    identifier: Name
  - columnName: TargetDomainName
    identifier: NTDomain
  entityType: Account
- fieldMappings:
  - columnName: TargetSid
    identifier: Sid
  entityType: Account
- fieldMappings:
  - columnName: Computer
    identifier: FullName
  - columnName: HostName
    identifier: HostName
  - columnName: HostNameDomain
    identifier: NTDomain
  entityType: Host
severity: Medium

ARM