The system MUST flag .txt.txt files in email attachments or download folders for potential spoofing. 3. Implementation Logic Detection: Scan for file extension regex: ^.*\.txt\.txt$ Handling Rule:
if filename.endswith(".txt.txt"): safe_filename = filename.replace(".txt.txt", ".txt") # Log incident for user warn_user("Double extension detected. Renaming for safety.") Use code with caution. Copied to clipboard .txt.txt
Default text editors (e.g., Notepad, TextEdit) SHOULD open .txt.txt files directly. The system MUST flag