Email Threats Explained: What is Malware?

When you open up your email to check your inbox, does malware and the serious threat that it poses to you and your company on a daily basis ever cross your mind? It certainly should.

Malware, a term that describes any program or file that is harmful to a computer user, does not discriminate: attacks can target anyone. However, research shows that 58% of malware attacks are directed at small business. And the consequences of a successful malware attack aren’t pretty. According to Accenture, the average cost in lost productivity of a malware attack is 50 days. For any business, this amount of downtime would have severe consequences.

Malware attacks can also have serious implications for society as a whole. Just a few days ago, a ransomware attack caused three hospitals in Alabama to turn patients away. Because the hospitals have limited ability to use their computer systems, they are unable to take new patients. And, sadly, this is not unusual. Over 75% of the healthcare industry has been infected with malware over the past year. Last week, another devastating malware attack left Sandusky County without access to their servers. A week later, the county’s servers are slowly being restored.

Although different malware variants have different methods for spreading and infecting computers, 92% of malware is delivered via email. Because email plays a pivotal role in business and society, we are all at risk of getting hit with malware. However, by implementing a comprehensive, multi-tiered email security gateway, users can significantly mitigate this risk.

What is malware and how does it work?

Malware encompasses all software that is designed to disrupt, damage or gain unauthorized access to a computer system. Malware can perform various detrimental functions which include encrypting or deleting sensitive data, stealing, hijacking or altering central computing functions and monitoring users’ activity without their permission. Common types of malware include viruses, worms, trojans, ransomware, fileless malware, adware and spyware.

The method by which malware spreads and infects computers and networks varies case by case. Malware is commonly delivered as a malicious attachment or link in a phishing email. Most malware email attachments include code or exploits which cause your computer to download more malware from the Internet. Some malicious programs can be delivered via a USB drive. Others spread over the Internet through drive-by downloads, which automatically download malicious programs without users’ knowledge or approval. In malware attacks, threat actors frequently utilize a command-and-control server which allows them to communicate with and remotely control infected systems, as well as to steal sensitive data from compromised devices.

Malware attacks are becoming increasingly sophisticated and difficult to combat. The most dangerous attacks utilize advanced social engineering techniques to penetrate and compromise systems. Once a system is compromised, sensitive data can be stolen and serious damage can be done before an attack is detected.

How to Recognize a Malware Email:

Knowing the common signs of a malware email is critical in protecting yourself and your company. Some “red flags” that indicate that an email may contain malware include: 

• Suspicious sender’s email address: If the sender's address is unfamiliar or doesn't match an expected address for a company, then there is a good chance that it is a malware email.
• Generic greeting: If the email begins with a generic greeting like “Dear Customer”, it may be malware or a phishing attempt.
• Email subject or attachment contains your username: The Subject field of a malware email may either contain your username or be blank. Malicious attachments may also contain your username in the filename.
• Enticement to download an attachment or click on a link: Many emails containing malware will encourage you to either download an attachment or follow a link which leads to malware. Remember: Emails about package delivery problems have no good reason to require you to open an attachment. If they were emailing you about a legitimate delivery problem they would inform you in the body of the email. 
• Suspicious attachment: If the email contains a suspicious attachment (such as a file with the extensions .doc, .zip, .xls, .js, .pdf, .ace, .arj, .wsh, .scr, .exe, .com, .bat, or other Microsoft Office file types), then it may be malware.
• Warning, threat or sense of urgency: Malware emails often attempt to get recipients to act quickly, before they have had adequate time to think things through. Be very wary if an email encourages you to download an attachment in order to solve a problem.
• Undisclosed or unlisted recipients: If the email recipient list shows either undisclosed or unlisted recipients or an email address other than yours, then it may be a malware email.
• Plain text/absence of logos: Most authentic emails are written with HTML and contain a mixture of text, logos and images. Malware emails tend to have plain formatting and rarely contain images.
• Unexpected attachment contents: If you do open an attachment and the contents are either empty or significantly different from what you expected, it may be malware.

Best Practices for Preventing a Successful Malware Attack:

Awareness and education are critical aspects of malware protection. Implementing these email security best practices will reduce your chances of suffering the consequences of a successful malware attack:

• Think before you act: Be wary of emails that urge you to act immediately or warn of negative consequences if you do not do so. Are you familiar with the sender? Do attachments or links included in the email appear to be suspicious in any way?
• Avoid suspicious websites: Malware attacks frequently involve spoofed websites. If anything about a website looks suspicious, be cautious and do not enter any sensitive data.
• Review software carefully before downloading: Prior to installing new software, look into the program and its reviews to ensure it is legitimate.
• Make sure all security patches and updates are installed: Install updates and patches as soon as possible to protect against malware and other digital threats. Turn on automatic updates whenever possible.
• Choose strong, unique passwords: It is critical that you use strong, unique passwords for each of your accounts. Enable two factor authentication (2FA) whenever possible.
• Limit application privileges: Because malware often needs full access to your computer to run properly, utilizing account controls to limit what a program or application can do without your permission is essential in protecting against malware. If you are notified of applications or software that are attempting to make changes to your system, take action immediately and seek the help of a security expert. It may be possible to stop the malware from installing.
• Turn on your firewall: Make sure that your firewall is correctly configured and turned on at all times. 
• Invest in a high-quality email security gateway solution: AntiVirus software alone is insufficient in protecting against malware attacks. Malicious email attachments are often small, highly customized and not widely spread, making them difficult for even the best antivirus software to detect. Only a comprehensive email security gateway solution that accurately identifies malicious emails and prevents them from reaching the inbox can effectively protect against malware.

How Guardian Digital can Help:

Guardian Digital recognizes that antivirus software and many conventiontional email security solutions are not enough to protect against malware. Guardian Digital EnGarde Email Security Gateway provides complete, end-to-end business email protection from malware and other email threats. EnGarde’s key benefits include:

• Neutralizes threats associated with malicious attachments and links
• End-to-end email encryption and secure delivery
• Authenticates every email delivered using DMARC, DKIM and SPF
• State-of-the-art heuristic technologies recognize malicious code and accurately identify and block highly targeted phishing attempts
• Protects employees against social engineering and impersonation attacks
• Multi-layered open-source architecture
• Fully-managed solution that can be seamlessly implemented into your business’s existing infrastructure 
• Exceptional 24/7/365 customer support

Want to Learn More about Malware and How to Protect Against it?

Do you have any questions about malware and malware protection that haven’t been addressed in this article? If so, please contact us and we would love to answer them!

Stay tuned for our next Email Threats Explained blog post: What is Spam Email?