It allows a large album to be split into multiple smaller parts, which was historically useful for sharing over slow internet connections or on sites with file size limits. Safety and Security Risks

Files may appear to be music (e.g., Album.rar ) but contain nested malicious files like .exe or .bat disguised with music icons. Legal and Industry Impact Is WinRAR safe? Everything you need to know - ExpressVPN

Vulnerabilities in extraction tools like WinRAR have historically allowed attackers to execute code simply by a user opening a "specially crafted" archive.