Detectionmediumtest

Visual Studio Code Tunnel Shell Execution

Detects the execution of a shell (powershell, bash, wsl...) via Visual Studio Code tunnel. Attackers can abuse this functionality to establish a C2 channel and execute arbitrary commands on the system.

Convert In Phoenix Studio

Open this Sigma rule in the converter with the YAML preloaded and ready for backend selection.

Launch

Nasreddine Bencherchali (Nextron Systems)Created Wed Oct 25f4a623c2-4ef5-4c33-b811-0642f702c9f1windows

Log Source

WindowsProcess Creation

ProductWindows← raw: windows

CategoryProcess Creation← raw: process_creation

Events generated when a new process is spawned on the system. Covers command-line arguments, parent/child relationships, and process metadata.

Detection Logic

detection:
    selection_parent:
        ParentImage|contains: '\servers\Stable-'
        ParentImage|endswith: '\server\node.exe'
        ParentCommandLine|contains: '.vscode-server' # Technically one can host its own local server instead of using the VsCode one. And that would probably change the name (requires further research)
    # Note: Child processes (ie: shells) can be whatever technically (with some efforts)
    selection_child_1:
        Image|endswith:
            - '\powershell.exe'
            - '\pwsh.exe'
        CommandLine|contains: '\terminal\browser\media\shellIntegration.ps1'
    selection_child_2:
        Image|endswith:
            - '\wsl.exe'
            - '\bash.exe'
    condition: selection_parent and 1 of selection_child_*