.. /vbc.exe

Star

Paths:

• C:\Windows\Microsoft.NET\Framework\v4.0.30319\vbc.exe
• C:\Windows\Microsoft.NET\Framework\v3.5\vbc.exe
• C:\Windows\Microsoft.NET\Framework\v2.0.50727\vbc.exe
• C:\Windows\Microsoft.NET\Framework64\v4.0.30319\vbc.exe
• C:\Windows\Microsoft.NET\Framework64\v3.5\vbc.exe
• C:\Windows\Microsoft.NET\Framework64\v2.0.50727\vbc.exe

Acknowledgements:

• Lior Adar
• Hai Vaknin(Lux)

Detections:

• Sigma: https://github.com/SigmaHQ/sigma/blob/683b63f8184b93c9564c4310d10c571cbe367e1e/rules/windows/process_creation/proc_creation_win_lolbin_visual_basic_compiler.yml
• Elastic: https://github.com/elastic/detection-rules/blob/61afb1c1c0c3f50637b1bb194f3e6fb09f476e50/rules/windows/defense_evasion_dotnet_compiler_parent_process.toml

Compile

1. Binary file used by .NET to compile Visual Basic code to an executable.

   vbc.exe /target:exe {PATH_ABSOLUTE:.vb}

   Use case

   Compile attacker code on system. Bypass defensive counter measures.

   Privileges required

   User

   Operating systems

   Windows 7, Windows 10, Windows 11

   ATT&CK® technique

   T1127

2. Binary file used by .NET to compile Visual Basic code to an executable.

   vbc -reference:Microsoft.VisualBasic.dll {PATH_ABSOLUTE:.vb}

   Use case

   Compile attacker code on system. Bypass defensive counter measures.

   Privileges required

   User

   Operating systems

   Windows 7, Windows 10, Windows 11

   ATT&CK® technique

   T1127