Detection rules › Sigma
Suspicious Schtasks Execution AppData Folder
Detects the creation of a schtask that executes a file from C:\Users<USER>\AppData\Local
MITRE ATT&CK coverage
| Tactic | Techniques |
|---|---|
| Execution | T1053.005 Scheduled Task/Job: Scheduled Task, T1059.001 Command and Scripting Interpreter: PowerShell |
| Persistence | T1053.005 Scheduled Task/Job: Scheduled Task |
| Privilege Escalation | T1053.005 Scheduled Task/Job: Scheduled Task |
Event coverage
| Provider | Event | Title |
|---|---|---|
| Sysmon | Event ID 1 | Process creation |
| Security-Auditing | Event ID 4688 | A new process has been created. |
Rule body yaml
title: Suspicious Schtasks Execution AppData Folder
id: c5c00f49-b3f9-45a6-997e-cfdecc6e1967
status: test
description: 'Detects the creation of a schtask that executes a file from C:\Users\<USER>\AppData\Local'
references:
- https://thedfirreport.com/2022/02/21/qbot-and-zerologon-lead-to-full-domain-compromise/
author: pH-T (Nextron Systems), Nasreddine Bencherchali (Nextron Systems)
date: 2022-03-15
modified: 2022-07-28
tags:
- attack.privilege-escalation
- attack.execution
- attack.persistence
- attack.t1053.005
- attack.t1059.001
logsource:
product: windows
category: process_creation
detection:
selection:
Image|endswith: '\schtasks.exe'
CommandLine|contains|all:
- '/Create'
- '/RU'
- '/TR'
- 'C:\Users\'
- '\AppData\Local\'
CommandLine|contains:
- 'NT AUT' # This covers the usual NT AUTHORITY\SYSTEM
- ' SYSTEM ' # SYSTEM is a valid value for schtasks hence it gets it's own value with space
filter:
# FP from test set in SIGMA
ParentImage|contains|all:
- '\AppData\Local\Temp\'
- 'TeamViewer_.exe'
Image|endswith: '\schtasks.exe'
CommandLine|contains: '/TN TVInstallRestore'
condition: selection and not filter
falsepositives:
- Unknown
level: high
Stages and Predicates
Stage 0: condition
selection and not filterStage 1: selection
selection:
Image|endswith: '\schtasks.exe'
CommandLine|contains|all:
- '/Create'
- '/RU'
- '/TR'
- 'C:\Users\'
- '\AppData\Local\'
CommandLine|contains:
- 'NT AUT'
- ' SYSTEM '
Stage 2: not filter
filter:
ParentImage|contains|all:
- '\AppData\Local\Temp\'
- 'TeamViewer_.exe'
Image|endswith: '\schtasks.exe'
CommandLine|contains: '/TN TVInstallRestore'
Exclusions
Top-level NOT(...) conjuncts: predicates this rule actively suppresses.
| Field | Kind | Excluded values |
|---|---|---|
CommandLine | match | /TN TVInstallRestore |
Image | ends_with | \schtasks.exe |
ParentImage | match | TeamViewer_.exe |
ParentImage | match | \AppData\Local\Temp\ |
Indicators
Each row is a field, operator, and value that the rule matches. The corpus column counts how many other rules in the catalog look for the same combination: high numbers point to widely-used, community-vetted indicators. Blank or 1 shows that the indicator is specific to this rule.
| Field | Kind | Values |
|---|---|---|
CommandLine | match |
|
Image | ends_with |
|