You may already be aware that you should not open email attachments with an extension such as ".exe", but did you know that even PDFs or Word Documents can be rendered unsafe to open? Opening these attachments from senders with malicious intent can cause your computer (and any networks to which you are connected) to be compromised, hacked or even riddled with ransomware.
 
What are the unsafe file types to look out for?  This question is better answered by listing file types that are generally considered to be safe to open. The truth is that almost all file types are at risk of being “booby-trapped” to attack your computer or device.
 
 The general rule is to NEVER open an email attachment if you do not know who it came from or why you received it.

How can I tell if an attachment is safe to open?

• Ask yourself: Was I expecting to receive this attachment, and did it come from who I would expect it to come from? Check email addresses for any “red flags” that may indicate the email address has been spoofed or faked.
• Never open an email attachment if you don’t recognize the sender that it came from.
• If you recognize the person or email address sending you the file, but it was still unexpected, contact them first through a different form of communication (such as by phone) to ask them if they intended to send you the file.

Stop Look Think

- Don't be fooled
The KnowBe4 Security Team
KnowBe4.com