Nasreddine Bencherchali
598d29f811
chore: change tags, date, modified fields to comply with v2 of the Sigma spec. chore: update the related type from `obsoletes` to `obsolete`. chore: update local json schema to the latest version.
73 lines
2.1 KiB
YAML
73 lines
2.1 KiB
YAML
title: Suspicious Modification Of Scheduled Tasks
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id: 1c0e41cd-21bb-4433-9acc-4a2cd6367b9b
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related:
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- id: 614cf376-6651-47c4-9dcc-6b9527f749f4 # Security-Audting Eventlog
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type: similar
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status: test
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description: |
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Detects when an attacker tries to modify an already existing scheduled tasks to run from a suspicious location
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Attackers can create a simple looking task in order to avoid detection on creation as it's often the most focused on
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Instead they modify the task after creation to include their malicious payload
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references:
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- Internal Research
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- https://learn.microsoft.com/en-us/windows-server/administration/windows-commands/schtasks
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author: Nasreddine Bencherchali (Nextron Systems)
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date: 2022-07-28
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modified: 2022-11-18
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tags:
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- attack.execution
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- attack.t1053.005
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logsource:
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product: windows
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category: process_creation
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detection:
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selection_schtasks:
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Image|endswith: '\schtasks.exe'
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CommandLine|contains|all:
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- ' /Change '
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- ' /TN '
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selection_susp_locations:
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CommandLine|contains:
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- '\AppData\Local\Temp'
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- '\AppData\Roaming\'
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- '\Users\Public\'
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- '\WINDOWS\Temp\'
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- '\Desktop\'
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- '\Downloads\'
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- '\Temporary Internet'
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- 'C:\ProgramData\'
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- 'C:\Perflogs\'
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- '%ProgramData%'
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- '%appdata%'
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- '%comspec%'
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- '%localappdata%'
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selection_susp_images:
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CommandLine|contains:
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- 'regsvr32'
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- 'rundll32'
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- 'cmd /c '
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- 'cmd /k '
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- 'cmd /r '
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- 'cmd.exe /c '
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- 'cmd.exe /k '
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- 'cmd.exe /r '
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- 'powershell'
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- 'mshta'
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- 'wscript'
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- 'cscript'
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- 'certutil'
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- 'bitsadmin'
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- 'bash.exe'
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- 'bash '
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- 'scrcons'
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- 'wmic '
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- 'wmic.exe'
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- 'forfiles'
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- 'scriptrunner'
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- 'hh.exe'
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- 'hh '
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condition: all of selection_*
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falsepositives:
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- Unknown
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level: high
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