Suspicious Use of CSharp Interactive Console

 1title: Suspicious Use of CSharp Interactive Console
 2id: a9e416a8-e613-4f8b-88b8-a7d1d1af2f61
 3status: test
 4description: Detects the execution of CSharp interactive console by PowerShell
 5references:
 6    - https://redcanary.com/blog/detecting-attacks-leveraging-the-net-framework/
 7author: Michael R. (@nahamike01)
 8date: 2020-03-08
 9modified: 2022-07-14
10tags:
11    - attack.execution
12    - attack.defense-evasion
13    - attack.t1127
14logsource:
15    category: process_creation
16    product: windows
17detection:
18    selection:
19        Image|endswith: '\csi.exe'
20        ParentImage|endswith:
21            - '\powershell.exe'
22            - '\pwsh.exe'
23            - '\powershell_ise.exe'
24        OriginalFileName: 'csi.exe'
25    condition: selection
26falsepositives:
27    - Possible depending on environment. Pair with other factors such as net connections, command-line args, etc.
28level: high

References

• Detecting attacks leveraging the .NET Framework | Red Canary

  

  The .NET framework includes rich offensive capabilities that adversaries aren’t yet using, but we’ve been thinking about detection anyway.

  
  Read More

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