Opening the file can trigger a script or exploit a vulnerability in your archive manager (like WinRAR or 7-Zip).

It likely contains an executable file ( .exe , .scr , .vbs ) masquerading as a document, invoice, or technical report.

A security vulnerability related to the GitHub Enterprise Server .

The file extension .rar is a compressed archive. It is a common delivery method for malware because:

Malicious code is often hidden inside the archive to bypass simple email scanners.