Sdelete deployed via GPO and run recursively (ASIM Version)

Hunt Hypothesis

‘This query looks for the Sdelete process being run recursively after being deployed to a host via GPO. Attackers could use this technique to deploy Sdelete to multiple host and delete data on them.

KQL Query

_Im_ProcessEvent
| where EventType =~ "ProcessCreated"
| where Process endswith "svchost.exe"
| where CommandLine has "-k GPSvcGroup" or CommandLine has "-s gpsvc"
| extend timekey = bin(TimeGenerated, 1m)
| project timekey, ActingProcessId, Dvc
| join kind=inner (
  _Im_ProcessEvent
  | where EventType =~ "ProcessCreated"
  | where Process =~ "sdelete.exe" or CommandLine has "sdelete"
  | where ActingProcessName endswith "svchost.exe"
  | where CommandLine has_all ("-s", "-r")
  | extend timekey = bin(TimeGenerated, 1m)
  ) 
  on $left.ActingProcessId == $right.ParentProcessId, timekey, Dvc
| extend AccountName = tostring(split(ActorUsername, @'\')[1]), AccountNTDomain = tostring(split(ActorUsername, @'\')[0])
| extend HostName = tostring(split(Dvc, ".")[0]), DomainIndex = toint(indexof(Dvc, '.'))
| extend HostNameDomain = iff(DomainIndex != -1, substring(Dvc, DomainIndex + 1), Dvc)
| project-away DomainIndex

Analytic Rule Definition

id: 30c8b802-ace1-4408-bc29-4c5c5afb49e1
name: Sdelete deployed via GPO and run recursively (ASIM Version)
description: |
  'This query looks for the Sdelete process being run recursively after being deployed to a host via GPO. Attackers could use this technique to deploy Sdelete to multiple host and delete data on them.
    This query uses the Advanced Security Information Model. Parsers will need to be deployed before use: https://docs.microsoft.com/azure/sentinel/normalization'
severity: Medium
requiredDataConnectors: []
queryFrequency: 1d
queryPeriod: 1d
triggerOperator: gt
triggerThreshold: 0
tactics:
  - Impact
relevantTechniques:
  - T1485
tags:
  -
query: |
  _Im_ProcessEvent
  | where EventType =~ "ProcessCreated"
  | where Process endswith "svchost.exe"
  | where CommandLine has "-k GPSvcGroup" or CommandLine has "-s gpsvc"
  | extend timekey = bin(TimeGenerated, 1m)
  | project timekey, ActingProcessId, Dvc
  | join kind=inner (
    _Im_ProcessEvent
    | where EventType =~ "ProcessCreated"
    | where Process =~ "sdelete.exe" or CommandLine has "sdelete"
    | where ActingProcessName endswith "svchost.exe"
    | where CommandLine has_all ("-s", "-r")
    | extend timekey = bin(TimeGenerated, 1m)
    ) 
    on $left.ActingProcessId == $right.ParentProcessId, timekey, Dvc
  | extend AccountName = tostring(split(ActorUsername, @'\')[1]), AccountNTDomain = tostring(split(ActorUsername, @'\')[0])
  | extend HostName = tostring(split(Dvc, ".")[0]), DomainIndex = toint(indexof(Dvc, '.'))
  | extend HostNameDomain = iff(DomainIndex != -1, substring(Dvc, DomainIndex + 1), Dvc)
  | project-away DomainIndex
entityMappings:
  - entityType: Account
    fieldMappings:
      - identifier: FullName
        columnName: ActorUsername
      - identifier: Name
        columnName: AccountName
      - identifier: NTDomain
        columnName: AccountNTDomain
  - entityType: Host
    fieldMappings:
      - identifier: FullName
        columnName: Dvc
      - identifier: HostName
        columnName: HostName
      - identifier: DnsDomain
        columnName: HostNameDomain
  - entityType: IP
    fieldMappings:
      - identifier: Address
        columnName: DvcIpAddr
version: 1.0.6
kind: Scheduled
metadata:
    source:
        kind: Community
    author:
        name: Microsoft Security Research
    support:
        tier: Community
    categories:
        domains: [ "Security - Threat Protection" ]

MITRE ATT&CK Context

• Tactic: Impact
• Technique: T1485 — Data Destruction

  Adversaries may destroy data and files on specific systems or in large numbers on a network to interrupt availability to systems, services, and network resources. Data destruction is likely to render

Validation (Atomic Red Team)

• T1485 — Data Destruction

References

• Source Query