41 lines
1014 B
YAML
41 lines
1014 B
YAML
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title: Suspicious Double Extension
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author: Florian Roth (rule), @blu3_team (idea)
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date: 2019/06/26
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description: Detects suspicious use of an .exe extension after a non-executable file
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extension like .pdf.exe, a set of spaces or underlines to cloak the executable file
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in spear phishing campaigns
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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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Image:
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- '*.doc.exe'
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- '*.docx.exe'
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- '*.xls.exe'
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- '*.xlsx.exe'
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- '*.ppt.exe'
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- '*.pptx.exe'
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- '*.rtf.exe'
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- '*.pdf.exe'
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- '*.txt.exe'
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- '* .exe'
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- '*______.exe'
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condition: (SELECTION_1 and SELECTION_2)
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falsepositives:
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- Unknown
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id: 1cdd9a09-06c9-4769-99ff-626e2b3991b8
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level: critical
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logsource:
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category: process_creation
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product: windows
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references:
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- https://blu3-team.blogspot.com/2019/06/misleading-extensions-xlsexe-docexe.html
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- https://twitter.com/blackorbird/status/1140519090961825792
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status: experimental
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tags:
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- attack.initial_access
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- attack.t1566.001
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- attack.t1193
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ruletype: SIGMA
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