Email is a way of life in most business and is often one of those tools we take for granted. We all feel the pain when it is down as for many it is a key part of their job. It’s also an extremely powerful tool that allows us to not only send and receive messages and meeting request, but also attachments. This is where email becomes dangerous to both you and your organization. Most organizations take some level of effort to protect the computer and network from these potentially dangerous attachments with varying levels of success. However there are practical steps that you can take to help ensure that a dangerous email attachment does not infect your organization.
Why can email attachments be dangerous?
Some of the characteristics that make email attachments convenient and popular are also the ones that make them a common tool for attackers:
- Attachments can pose a threat when it is an executable and/or script.
- Attachments can come in the form of a virus which infects your computer and potentially automatically forwards itself to everyone in your address book, quickly infecting your entire organization as well as others in your address book. This could include ransomware, data theft, etc.
- Attachments could be used to data mine your emails for personal or business information that can be used to harm you or your organization.
What steps can you take to protect yourself and others in your address book?
- Be wary of unsolicited attachments, even from people you know – Just because an email message looks like it came from your mom, grandma, or boss doesn’t mean that it did. Many viruses can “spoof” the return address, making it look like the message came from someone else. If you can, check with the person who supposedly sent the message to make sure it’s legitimate before opening any attachments. This includes email messages that appear to be from your ISP or software vendor and claim to include patches or anti-virus software. ISPs and software vendors do not send patches or software via email.
- Keep software up to date – Install software patches so that attackers can’t take advantage of known problems or vulnerabilities (see Understanding Patches for more information). Many operating systems offer automatic updates. If this option is available, you should enable it.
- Trust your instincts – If an email or email attachment seems suspicious, don’t open it, even if your anti-virus software indicates that the message is clean. Attackers are constantly releasing new viruses, and the anti-virus software might not have the signature. At the very least, contact the person who supposedly sent the message to make sure it’s legitimate before you open the attachment. However, especially in the case of forwards, even messages sent by a legitimate sender might contain a virus. If something about the email or the attachment makes you uncomfortable, there may be a good reason. Don’t let your curiosity put your computer at risk.
- Turn off the option to automatically download attachments – To simplify the process of reading email, many email programs offer the feature to automatically download attachments. Check your settings to see if your software offers the option, and make sure to disable it.
- Save and scan any attachments before opening them – If you have to open an attachment before you can verify the source, take the following steps:
- Be sure the signatures in your anti-virus software are up to date.
- Save the file to your computer or a disk.
- Manually scan the file using your anti-virus software.
- If the file is clean and doesn’t seem suspicious, go ahead and open it.