Do not attempt to "see what's inside."
Monitoring your keystrokes or accessing your webcam. Ransomware: Locking your files and demanding payment. What to do if you received it
If it came from a friend, their account has likely been hacked. Use a different communication method (like a text or phone call) to let them know.
Random strings of numbers followed by .rar or .zip are major red flags.
Warning: If You Receive "received_535813991618116.rar", Don’t Open It
Stealing your login info for banks and social media.
This file is part of a social engineering tactic. Attackers often compromise social media accounts (like Facebook) and send this file to the victim's entire contact list. Because the message comes from a "trusted" source, users are much more likely to download and open it. Why is it dangerous?