This detection rule identifies suspicious .csproj files that are sent as attachments in incoming messages. Specifically, it looks for file attachments with a .csproj extension. The rule is activated if the .csproj file contains certain commands that are typically associated with malicious behavior, such as invoking DllImport and CreateProcess. These commands are often used by malware to execute arbitrary processes or run malicious code. Given the nature of .csproj files—typically used in .NET development—it highlights potential risks where traditional development files may be weaponized to deliver malware or ransomware. The detection method involves file analysis, scanning for specific strings within the exposed content of the files, making it crucial for security measures in environments susceptible to malware infiltration via email or other communication channels.