Since there is no public community write-up currently indexed for a file with this exact name, I can provide a general and the standard steps you would take to solve a challenge involving this specific RAR archive: 1. File Identification & Metadata
: If it contains a .img or .vmdk , mount it or use Autopsy to find deleted files. MBFSE30.rar
: If there is a .pcap , open it in Wireshark and filter by http or dns to find the flag. Since there is no public community write-up currently