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How email filtering helps defend against malware and ransomware

(Image credit: Image Credit: Evannovostro / Shutterstock)

Spam has been around since the earliest days of email. While many spam messages are poorly written and reek of malicious intent, others are less conspicuous. Cyber-criminals can slyly embed malware and ransomware into emails that can do serious damage if opened. Fortunately, today’s email filtering systems do an excellent job at finding and isolating these messages. Here we’ll examine the details of email filtering and why they should never be taken for granted. 

The Rise of Malware Attacks 

Malware is short for “malicious software,” programs that allow someone to access your computer and track what you are doing. Attackers send emails to users with a link to something attractive to click on, such as a news event or interesting video. The link takes users to a legitimate web page, where they’re asked to download a program to view the content. This program is the malware. (It should be noted that cyber-criminals also turn to social media and browser pop-ups to send messages to users.) 

Once the malware is installed, the cyber-criminal can see what you’re doing on your computer and steal personal information. Credit card fraud, identity theft, and selling your information to other cyber-criminals are just a few of the potential results. 

According to a study conducted by SpiceWorks, 54 percent of IT professionals said they were either “very concerned” or “extremely concerned” about malware. This makes sense, as 51 percent of respondents claimed to have experienced a malware attack. Fortunately, these professionals understand the risk, and 32 percent of respondents stated they would spend more cash on content filtering as a security solution. 

The Rise of Ransomware Attacks 

Ransomware is a type of malware that blocks or limits user access to their computer or certain files until a sum of money is paid. After the email is opened, a message appears demanding a ransom. Attackers can build the message to look as though it has been sent by the police. To make matters worse, paying the ransom is no guarantee that the attackers will reinstate your access. 

It’s easy to see why this type of attack is popular and on the rise. A study released this year by KnowB34 found that 38 percent of surveyed companies were victims of ransomware attacks compared to 20 percent in 2014. Interestingly, 61 percent of respondents also felt that email attachments posed the largest ransomware threat, up from 47 percent in 2014. 

Surely, ransomware attacks are most common for small businesses with fewer security measures in place, right? Unfortunately, businesses of all sizes are targeted by cyber-criminals. Mid-sized companies are hit hardest, accounting for 54 percent of the attacks covered in the survey. 

Ransomware is an effective tactic that poses real threats to businesses of all sizes. Just because your company hasn’t been hit yet doesn’t mean it can’t happen. Indeed, it’s this false sense of security that makes businesses less aware of—and more vulnerable to—potential threats that come their way. 

Email Services Filter Against Attacks 

Email filters can provide a quick yet dependable guard against malware and ransomware attacks. They work in two ways. First, filters capture spam messages and quarantine them. Spam messages are typically sent out in email blasts and try to sell products. Email services like Gmail, Yahoo, and include a “Spam” folder that users can review. These services also provide details on why these messages were captured by the spam filter (Gmail, for example, lists the file types it doesn’t allow to be sent as attachments). Sometimes legitimate messages get caught by these filters, but this means they contained wording or files typically associated with spam. 

The second way email filtering works is by scanning for malicious code. Today’s email filters are can scan documents, executable files, and zip files before they’re opened. While spam messages are easier to identify based on their content, malware messages typically have convincing subject lines which increase their likelihood of being opened. Let’s take Gmail as an example: Have you ever looked in your spam folder and found an email from an unknown sender with an attachment? This is good email filtering at work, as Gmail detected the attachment could be malware. 

Email Security Solutions Add Additional Protection 

Even though today’s popular email services include spam and antivirus filters, they aren’t perfect. Gmail, for example, can’t delete an attached virus. However, there are other, more secure, email services that account for this type of security gap. A secure email solution can scan for malware, ransomware, and phishing scams, and even look for and block suspicious URLs. Most of these solutions will integrate with your company’s email service as well as allow customized reporting and enhanced detection capabilities. 

While protecting against known threats is important, security solutions must be sophisticated enough to detect emerging threats and block accordingly. As anti-hacking measures increase in sophistication, cyber-criminals are developing new ways to overcome them. Superior email security solutions are always conducting research and using the latest intelligence to identify new threats—allowing your company to update its rules and policies to ensure all threats are filtered accordingly. 

Educating Employees on Email Best Practices 

Of course, email filtering is only part of the process. Employees should be properly trained on what to look out for when working with their email accounts. The filters provided by today’s email services and security solutions are great at catching most harmful messages, but no system is perfect. While you may know the threats of malware and ransomware, do your employees? Do they know not to click on unrecognizable links embedded in emails? What about emails that contain signs of phishing despite their convincing headlines? Combating threats means educating your workers. Hold training sessions that review your company’s best practices and send out periodic reminder emails. Cyber-criminals are never going to give up, yet putting up every defense possible will help keep them at bay. 

Image Credit: Evannovostro / Shutterstock

Erik Kangas
LuxSci founder Erik Kangas has an impressive mix of academic research and software architecture expertise, including: undergraduate degree from Case Western Reserve University in physics and mathematics, PhD from MIT in computational biophysics, senior software engineer at Akamai Technologies, and visiting professor in physics at MIT. Chief architect and developer at LuxSci since 1999, Erik focuses on elegant, efficient, and robust solutions for scalable email and web hosting services, with a primary focus on Internet security.