Scheduled Task Execution at Scale via GPO

## Triage and analysis

### Investigating Scheduled Task Execution at Scale via GPO

Group Policy Objects can be used by attackers to execute Scheduled Tasks at scale to compromise Objects controlled by a given GPO,
this is done by changing the contents of the `<GPOPath>\Machine\Preferences\ScheduledTasks\ScheduledTasks.xml` file.

#### Possible investigation steps:
- This attack abuses a legitimate mechanism of the Active Directory, so it is important to determine whether the activity is legitimate
and the administrator is authorized to perform this operation.
- Retrieve the contents of the `ScheduledTasks.xml` file, check the `<Command>` and `<Arguments>` XML tags for any potentially malicious
commands and binaries.
- If the action is suspicious for the user, check for any other activities done by the user in the last 48 hours.

### False Positive Analysis
- Verify if the execution is allowed and done under change management, and if the execution is legitimate.

### Related Rules
- Group Policy Abuse for Privilege Addition
- Startup/Logon Script added to Group Policy Object

### Response and Remediation
- Immediate response should be taken to validate activity, investigate and potentially isolate activity to prevent further
post-compromise behavior.

## Config

The 'Audit Detailed File Share' audit policy is required be configured (Success Failure).
Steps to implement the logging policy with with Advanced Audit Configuration:
```
Computer Configuration >
Policies >
Windows Settings >
Security Settings >
Advanced Audit Policies Configuration >
Audit Policies >
Object Access >
Audit Detailed File Share (Success,Failure)
```

The 'Audit Directory Service Changes' audit policy is required be configured (Success Failure).
Steps to implement the logging policy with with Advanced Audit Configuration:
```
Computer Configuration >
Policies >
Windows Settings >
Security Settings >
Advanced Audit Policies Configuration >
Audit Policies >
DS Access >
Audit Directory Service Changes (Success,Failure)
```