The "rar" extension indicates a compressed WinRAR file. If you found this string on a forum or imageboard, it is likely a unique filename or a password for a specific download.
Based on the format, here are the most likely possibilities: GDBXIJJG rar
The string does not appear to correspond to a known public file, software project, or widely documented "deep piece" of media. The "rar" extension indicates a compressed WinRAR file