Bitcoin Black

Extension Purpose

This extension claims to be a premium dark theme inspired by Bitcoin, providing black backgrounds and orange/gold accents for focused coding sessions. However, the code does not implement any theme logic or VS Code theme APIs. Instead, it performs actions unrelated to theming.

Code Behavior and API Usage

• Logging:

  • The extension logs activation, extension path, and other events to a file named btc-ext.log in the system temporary directory (e.g., C:\Windows\Temp\btc-ext.log).
  • Uses Node.js fs.appendFileSync for logging.

• Script Execution:

  • On activation, the extension checks for the existence of a marker file at C:\Windows\Temp\Lightshot\.done (or %TEMP%\Lightshot\.done).
  • If the marker file does not exist, it attempts to execute a batch script located at scripts/run.bat within the extension directory using cmd.exe.
  • The process is spawned in detached mode, with no standard IO, and is hidden from the user (windowsHide: true).
  • No output is captured or shown to the user.

• File System Activity:

  • Reads and writes to files in the system temporary directory.
  • Checks for the existence of a marker file and a batch script.

• No Network Activity:

  • There are no network requests or URLs/domains present in the code.

Potentially Suspicious Behavior

• Process Execution:
  • The extension spawns a new process (cmd.exe) to run a batch script (run.bat).
  • The batch script's contents are not provided, so its behavior is unknown.
• Persistence/Marker:
  • Uses a marker file to ensure the script is only executed once per environment.
• No Theme Functionality:
  • The code does not implement any theme-related features, which is inconsistent with the extension's description.

Files Written

• C:\Windows\Temp\btc-ext.log (or %TEMP%\btc-ext.log): Log file created/appended by the extension.

Summary

While the code does not show direct evidence of malicious activity (such as data exfiltration, privilege escalation, or registry modification), the execution of an external batch script on activation—especially in an extension claiming to be a theme—is highly suspicious and not aligned with the stated purpose. The actual intent depends on the contents of scripts/run.bat, which are not included here.