mirror of
https://github.com/LOLBAS-Project/LOLBAS
synced 2024-12-27 23:37:58 +01:00
40 lines
2.1 KiB
YAML
40 lines
2.1 KiB
YAML
---
|
|
Name: Fsi.exe
|
|
Description: 64-bit FSharp (F#) Interpreter included with Visual Studio and DotNet Core SDK.
|
|
Author: Jimmy (@bohops)
|
|
Created: 2021-09-26
|
|
Commands:
|
|
- Command: fsi.exe c:\path\to\test.fsscript
|
|
Description: Execute F# code via script file
|
|
Usecase: Execute payload with Microsoft signed binary to bypass WDAC policies
|
|
Category: AWL Bypass
|
|
Privileges: User
|
|
MitreID: T1059
|
|
OperatingSystem: Windows 10 2004 (likely previous and newer versions as well)
|
|
- Command: fsi.exe
|
|
Description: Execute F# code via interactive command line
|
|
Usecase: Execute payload with Microsoft signed binary to bypass WDAC policies
|
|
Category: AWL Bypass
|
|
Privileges: User
|
|
MitreID: T1059
|
|
OperatingSystem: Windows 10 2004 (likely previous and newer versions as well)
|
|
Full_Path:
|
|
- Path: C:\Program Files\dotnet\sdk\[sdk version]\FSharp\fsi.exe
|
|
- Path: C:\Program Files (x86)\Microsoft Visual Studio\2019\Professional\Common7\IDE\CommonExtensions\Microsoft\FSharp\fsi.exe
|
|
Code_Sample:
|
|
- Code: https://gist.github.com/NickTyrer/51eb8c774a909634fa69b4d06fc79ae1
|
|
Detection:
|
|
- Elastic: https://github.com/elastic/detection-rules/blob/414d32027632a49fb239abb8fbbb55d3fa8dd861/rules/windows/defense_evasion_unusual_process_network_connection.toml
|
|
- Elastic: https://github.com/elastic/detection-rules/blob/414d32027632a49fb239abb8fbbb55d3fa8dd861/rules/windows/defense_evasion_network_connection_from_windows_binary.toml
|
|
- BlockRule: https://docs.microsoft.com/en-us/windows/security/threat-protection/windows-defender-application-control/microsoft-recommended-block-rules
|
|
- IOC: Fsi.exe execution may be suspicious on non-developer machines
|
|
- Sigma: https://github.com/SigmaHQ/sigma/blob/6b34764215b0e97e32cbc4c6325fc933d2695c3a/rules/windows/process_creation/proc_creation_win_lolbin_fsharp_interpreters.yml
|
|
Resources:
|
|
- Link: https://twitter.com/NickTyrer/status/904273264385589248
|
|
- Link: https://bohops.com/2020/11/02/exploring-the-wdac-microsoft-recommended-block-rules-part-ii-wfc-fsi/
|
|
Acknowledgement:
|
|
- Person: Nick Tyrer
|
|
Handle: '@NickTyrer'
|
|
- Person: Jimmy
|
|
Handle: '@bohops'
|