LOLBAS/yml/OSBinaries/Csc.yml

38 lines
2.2 KiB
YAML

---
Name: Csc.exe
Description: Binary file used by .NET Framework to compile C# code
Author: 'Oddvar Moe'
Created: 2018-05-25
Commands:
- Command: csc.exe -out:Output.exe File.cs
Description: Use csc.exe to compile C# code, targeting the .NET Framework, stored in File.cs and output the compiled version to Output.exe.
Usecase: Compile attacker code on system. Bypass defensive counter measures.
Category: Compile
Privileges: User
MitreID: T1127
OperatingSystem: Windows vista, Windows 7, Windows 8, Windows 8.1, Windows 10, Windows 11
- Command: csc -target:library File.cs
Description: Use csc.exe to compile C# code, targeting the .NET Framework, stored in File.cs and output the compiled version to a DLL file.
Usecase: Compile attacker code on system. Bypass defensive counter measures.
Category: Compile
Privileges: User
MitreID: T1127
OperatingSystem: Windows vista, Windows 7, Windows 8, Windows 8.1, Windows 10, Windows 11
Full_Path:
- Path: C:\Windows\Microsoft.NET\Framework\v4.0.30319\Csc.exe
- Path: C:\Windows\Microsoft.NET\Framework64\v4.0.30319\Csc.exe
- Path: C:\Windows\Microsoft.NET\Framework\v3.5\csc.exe
- Path: C:\Windows\Microsoft.NET\Framework64\v3.5\csc.exe
- Path: C:\Windows\Microsoft.NET\Framework\v2.0.50727\csc.exe
- Path: C:\Windows\Microsoft.NET\Framework64\v2.0.50727\csc.exe
Code_Sample:
- Code:
Detection:
- Sigma: https://github.com/SigmaHQ/sigma/blob/62d4fd26b05f4d81973e7c8e80d7c1a0c6a29d0e/rules/windows/process_creation/proc_creation_win_csc_susp_parent.yml
- Sigma: https://github.com/SigmaHQ/sigma/blob/62d4fd26b05f4d81973e7c8e80d7c1a0c6a29d0e/rules/windows/process_creation/proc_creation_win_csc_susp_folder.yml
- Elastic: https://github.com/elastic/detection-rules/blob/61afb1c1c0c3f50637b1bb194f3e6fb09f476e50/rules/windows/defense_evasion_dotnet_compiler_parent_process.toml
- Elastic: https://github.com/elastic/detection-rules/blob/82ec6ac1eeb62a1383792719a1943b551264ed16/rules/windows/defense_evasion_execution_msbuild_started_unusal_process.toml
- IOC: Csc.exe should normally not run as System account unless it is used for development.
Resources:
- Link: https://learn.microsoft.com/en-us/dotnet/csharp/language-reference/compiler-options/