Safety Tips for Handling Malicious Email Attachments | EasyDMARC

Safety Tips for Handling Malicious Email Attachments

7 Min Read
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Emails are the leading form of communication worldwide. But malicious email attachments are an everyday occurrence. So how do you deal with them? 

Emails with malicious attachments can spread viruses among networks and systems quite easily—without you even forwarding the email. Security experts and IT departments do their best to mitigate threats like phishing attacks, but they can’t do much if users aren’t educated about them. 

You may be wondering what malicious email attachments are exactly. The answer is pretty simple. They’re executable files disguised as PDFs, text files, word documents, zip files, etc. attached to email messages, and designed to unload malware onto your system with a single click. 

No network is 100% protected against these files. That’s why it’s so important to know everything you can about them. Cyber threat actors are always thinking up new ways to scam victims,  but malware-loaded emails aren’t going anywhere. 

So how do you protect your company and customers from such threats? 

Knowing which email attachments may contain something malicious is an excellent start—but it can be tricky. We discuss the best tips to handle malicious attachments below  Let’s dive in!

Set Up a Secure Environment

The common types of malicious attachments hackers use include self-replicating worms, trojans, ransomware, and other malware. Thus, a secure environment for your data and network is vital. 

Your email infrastructure plays a major role here. Make sure your antivirus software and firewall is up to date. A  solid Data Loss Prevention strategy is also important. 

However, the best way to secure your communications is by authenticating your domain using DMARC protocols.

DMARC authentication works alongside the two main verification policies used for email security, SPF and DKIM. With a proper DMARC setup, cybercriminals can’t use your company’s name, domain, and reputation to send malicious email attachments to unsuspecting victims.

DMARC protects your customers from scams, spoofs, and phishing emails while increasing your reputation as a sender. There are other security measures you can enforce, but domain authentication is one of the safest ways for recipients to filter malicious attachments.

Here are other ways to protect your organization from malicious email attachments:

Use Spam Filters

Spam filters are designed to help you keep malicious emails at bay, either by filtering their access into your network or blocking them. There are multiple spam filters in the market, but most ESPs have built-in defense mechanisms. Check the configuration settings to ensure no emails with malicious attachments enter your network.

Scan Incoming Emails

Scanning for malicious email attachments is a common practice these days. There are a few ways to go about this. First, verify the source of the email. Next, run a scan using antivirus software. After that, use the preview option offered by most ESPs. 

These previews are small thumbnails that allow you to see what type of file you’re receiving. If the file and the actual email seem legitimate, scan it once more and confirm receipt with the sender before opening it. 

Turn Off Automatic Downloads

A solid way to deal with malicious email attachments is by turning off automatic downloads. Many ESPs offer this feature for convenience but it can be dangerous. The same goes for messaging apps like WhatsApp, etc. It’s best to turn off this option and review your emails securely.

Stay Alert

Avoid falling prey to malicious email attachments by staying alert and combining security protocols with education. Your employees can help secure your network by following certain security practices. Here are some top tips to include in your cybersecurity policies:

Unsubscribe From Unsolicited Bulk Emails

By now, most emails are included in some form of database sold online. Your company’s email isn’t safe from this practice. Bulk emails can arrive in your inbox without notice. Many times it’s impossible to know if these messages include a dangerous email attachment

For the sake of keeping a safe environment, it’s best to unsubscribe from these mailing lists. Never give your email address to untrustworthy websites and avoid sharing your personal corporate email address with the public. If you buy a product or sign up for a service, use an alternate email just in case. 

Don’t Send Sensitive Information Over Email

You never know when someone is watching and using your confidential info to spread malicious email attachments

Once you send an email with personal information, you don’t know what the receiver will do with it. Never include information such as your full name, social security number, bank accounts, passwords, or other similar data. No service ever asks for this information, so be suspicious of any email that does.

Avoid Open Wi-Fi as Much as Possible

Public networks are one of the easiest ways to spread malicious email attachments. They’re a favorite playground for hackers to access loads of personal data. Cyber actors can use public networks to harvest usernames, email addresses, and login information. 

They’re also fertile ground for phishing and other cyberattacks loaded with malware. Most people are unaware of how unsafe public networks can be. If you must use a public wi-fi, try to avoid using any accounts storing sensitive information.   

Practice Good Password Hygiene

Password collectors and keystroke loggers are the most common types of malicious attachments hackers use. You can prevent these attacks by maintaining good password hygiene. 

Make sure to change your passwords frequently. The recommended lifespan of a password is three months. If this is too bothersome for you, then focus on building a strong password using a combination of sentences, different cases, special characters, and numbers. Investing in a credible password manager is also worthwhile.

Don’t Open Emails from Untrusted Sources

Many victims fall for cyberattacks because they don’t know which email attachments may contain something malicious. Most of these folks also open any email they get indiscriminately, without checking their source. 

Your team should never open emails if they don’t know the source. This applies to any email coming from an outside or inside source. All emails should be thoroughly examined, especially if they’re from an unknown sender It’s still wise to verify the email if it appears to come from someone known.

Advocate for DMARC in Your Organization

We’ve already mentioned a few things about DMARC protocols. With a strong DMARC policy in place, you’ll protect customers from receiving fraudulent messages in your company’s name that often contain malicious email attachments

You’ll become a trusted sender for all your clients, vendors, and business partners. They’ll know your emails are legitimate and come directly from the source. Cybercriminals won’t be able to spoof your domain to scam them, either.

Final Thoughts

Dealing with malicious email attachments is the bane of many IT teams’ and cybersecurity companies’ existence. As a business owner, you can prevent much of the damage inflicted by these attachments with education and security protocols

Setting up a DLP strategy can help keep your data and network safe. But the best way to prevent these attacks is by keeping your communications secure. There’s a lot you can do to avoid being affected by malicious email attachments.

Use the spam filters included in your ESP,  scan all incoming messages, and make sure your antivirus is updated and ready to analyze all attachments in your inbox. 

Use the preview system adopted by most email providers to look at the files in your emails. Keep an eye out for unsafe practices. Never send personal data in your emails, don’t use public networks, and create strong passwords.

You can always advocate for using DMARC policies in your company. It’s the safest way to keep your communications secure. Contact EasyDMARC to find out how we can make your email domain more secure—the easy way.

Various authors from EasyDMARC teams have contributed to our blog during company's lifetime. This author brings everyone together.


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