Recognize Potential Threats: Top 5 Malicious Email Attachment Types

The average person checks their email 15 times per day. Although much of your communication may have moved over to social media or messaging apps, emails are still an integral part of our lives. That’s why they are such a frequent target of hackers.

More than 1 in 3 Americans have either been hacked or had their identity stolen. Furthermore, 75% of businesses reported receiving scam emails. You may even have a dangerous email in your inbox right now. Learn how to keep your computer and mobile devices safe by recognizing these risky email attachment types.

Popular Attachments That Can Contain Malware

1.    ZIP

ZIP files are super handy. If you want to send a file by email, you usually must convert it to ZIP. Unlike other file types, though, you don’t know what could be hiding in there.

Last year, massive spam campaigns spread the dangerous GandCrab ransomware via zip files. This malware locked users out of critical data unless they paid $2000 (or more).

How did it happen? Users thought they were downloading innocuous ZIP files. But these files contained a JavaScript download. It could execute the malware before the user could delete it from their computer.

2.    Office Files Like Doc, XLSM, PPT

Most people don’t realize that Word and Excel files can be dangerous. They don’t know that hackers can hide malicious code even in the most innocent file types. For example, cybercriminals use both DOC and XLSM (an Excel file type) to deliver a nasty banking trojan known as TrickBot.

Hackers often use social engineering techniques when distributing such trojans. They claim to be tax authorities and encourage users to download tax documents attached to the email. But once the person downloads the file, it executes the Trojan. It then can harvest sensitive data off victims’ computers, including their banking and financial details.

3.    PDF

PDF is another prevalent file type that people use every day and wouldn’t think twice about. In 2018, hackers targeted American Express customers with PDF files. The phishing campaign tricked people into giving their login credentials and other account info on fake web pages.

How did it happen? Users got a “secure message” purportedly from the American Express Business Card Customer Security Team. But the link in the PDF file led to a malicious landing page that harvested user credentials. Everything about the scheme was professional. Thus, it could have tricked even the most cybersecurity conscious AMEX customers.

4.    ISO and IMG

Oddly enough, ISO and IMG attacks have been on the rise in the last few years. It is strange because ISO and IMG files are data layouts for CD and disc images. How can this be happening when fewer people than ever user disc drives?

Hackers have targeted emails, popular browsers, and file-sharing clients. They created info-stealing campaigns like AgentTesla to execute the malware on infected computers. It allowed hackers to gain access to the system and other sensitive information.

5.    Mac Files Like .a3m, a4m, .bin, .hqx, .rs

Despite the widespread misconception, hacks can and do happen to Macs. And since more people have made the switch to Apple, they’re happening now more than ever.

Moreover, most people have the misconception that Macs are safe against hackers. That’s why they don’t have the same digital security habits as Windows users. That’s why no matter the OS you use, always be on the lookout for threats.

How to Prevent Downloading Malicious Attachments

Email scams aren’t going away; they’re only going to increase in numbers. But you can enhance your defenses by recognizing malicious attachments. Following the best cybersecurity practices will help to do that.

Scan All Files Before Downloading

Take an extra few seconds and scan all files before you download them to your computer. Norton and Bitdefender have powerful email scanning tools.

You can also use tools like VirusTotal, which allows you to forward suspicious emails to a malware-scanning address. It will check the contents of the email for any dangerous malware and send you back the results. Then you know whether it’s safe to download the attachment or not.

Email to: [email protected]

Make sure you also scan all links before clicking on them. It is another common way cybercriminals target users.

Enable a VPN

Anytime you connect to the internet, you never know who may be watching. Hackers, advertisers, big corporations, ISPs, and other parties can track your activity. As you can imagine, it increases your vulnerability online.

VPNs create an encrypted tunnel between your device and the websites you visit online. It secures your data, preventing anybody from intercepting it. Best of all, they’re easy to use. After you install a VPN, turn it on and leave it running anytime you connect to the internet. Some advanced VPNs also have cybersecurity options and can protect you from malware, phishing, and other threats.

Email Threats are on the Rise

Email attacks are increasing. And hackers can turn any file type into a threat. That’s why you need to be alert when checking your inbox. Always scan received files, even if they look legit. Even if it’s your boss, who sent you the email. It’s better to waste a few seconds scanning a file than dealing with consequences of malware or a successful phishing scam.

About the author

Tirupati Gumpula

Hi, I'm a Tech Enthusiastic and founder of Popular technology blogsWay to Hunt. & Elite Tricks. Want to promote your brand? Email: [email protected]

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