44 lines
1.6 KiB
YAML
44 lines
1.6 KiB
YAML
title: Invoke-Obfuscation Obfuscated IEX Invocation
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author: Daniel Bohannon (@Mandiant/@FireEye), oscd.community
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date: 2019/11/08
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description: "Detects all variations of obfuscated powershell IEX invocation code\
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\ generated by Invoke-Obfuscation framework from the following code block \u2014\
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\ https://github.com/danielbohannon/Invoke-Obfuscation/blob/master/Out-ObfuscatedStringCommand.ps1#L873-L888"
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detection:
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SELECTION_1:
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EventID: 1
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SELECTION_2:
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CommandLine|re: \$PSHome\[\s*\d{1,3}\s*\]\s*\+\s*\$PSHome\[
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SELECTION_3:
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CommandLine|re: \$ShellId\[\s*\d{1,3}\s*\]\s*\+\s*\$ShellId\[
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SELECTION_4:
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CommandLine|re: \$env:Public\[\s*\d{1,3}\s*\]\s*\+\s*\$env:Public\[
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SELECTION_5:
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CommandLine|re: \$env:ComSpec\[(\s*\d{1,3}\s*,){2}
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SELECTION_6:
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CommandLine|re: \\\\*mdr\\\\*\W\s*\)\.Name
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SELECTION_7:
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CommandLine|re: \$VerbosePreference\.ToString\(
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SELECTION_8:
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CommandLine|re: \\\\String\]\s*\$VerbosePreference
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condition: (SELECTION_1 and (SELECTION_2 or SELECTION_3 or SELECTION_4 or SELECTION_5
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or SELECTION_6 or SELECTION_7 or SELECTION_8))
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falsepositives:
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- Unknown
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id: 4bf943c6-5146-4273-98dd-e958fd1e3abf
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level: high
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logsource:
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category: process_creation
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product: windows
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modified: 2020/09/01
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status: experimental
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tags:
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- attack.defense_evasion
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- attack.t1027
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- attack.execution
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- attack.t1059.001
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- attack.t1086
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yml_filename: win_invoke_obfuscation_obfuscated_iex_commandline.yml
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yml_path: /Users/user/Documents/YamatoSecurity/sigma/rules/windows/process_creation
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