How Good is Your Spam Filter, Really?

Cybersecurity | March 1, 2022

You want what’s best for your business, right? Then why are you still using a sub-par spam filter? 

Building your organization up to enterprise-level success requires more than just the right team members and mix of services – it requires the right protection, too. And while some email software comes complete with a decent spam filter baked in, not every inbox has what it takes to properly defend your sensitive data.  

Is yours one of them? 

From the good to the bad to the ugly, here’s what you need to know about selecting a decent spam filter.  

What is a Spam Filter? 

A spam filter is a program attached to your organization’s email software used to detect and sort unwanted or untrustworthy mail. Spam filters help to keep risky messages and bad actors out of your inbox, curbing potential phishing attacks, malware, and ransomware from entering your networks. 

While spam filters are a necessary security component for businesses of all shapes and sizes, it’s important to note that spam filters are largely reactive in nature and cannot protect the entire scope of your business alone. Rather, they should be seen as a vital tool in an otherwise large, comprehensive, and proactive cybersecurity protocol.  

How Does Spam Filtering Work? 

Traditionally, spam filters work by diverting all traffic to your account to run through a program before sorting into the inbox. This program scans each piece of mail for certain keywords, encryption, or other triggers to identify potentially threatening or malicious messages. Once identified, the filter will send cleared messages to your inbox and suspicious ones to your spam folder.  

The earliest iterations of spam filters simply matched the content of a given email to a list of keywords or phrases commonly used by cybercriminals. While there have been many advancements in today’s filtering technology, the premise has stayed largely the same; When a message comes in, your spam filter compares its contents to those of spam messages past and flags them down. For this reason, some legitimate emails are often flagged by accident.  

In recent years, newer programs have introduced a more heuristic approach to inbox filtering, using behavioral analytics to try and predict potential threats even when the message contains no known triggers. However, these technologies do not yet represent the whole spam filter market.  

Some of the most common types of spam filtering include: 

  • Content Filters – Content filters review the wording of a given email to determine whether or not that message is safe. 
  • Header Filters – Header filters examine the header of an email (including IP address) to suss out if the message was sent by a legitimate source. 
  • Blocklist Filters – Blocklist filters simply block emails sent by previously identified untrustworthy senders.  
  • Rule-Based Filters – Rule-based filters establish a set of pre-determined rules for secure emails and measure all incoming messages against those rules. 

What Email Software Already Has a Spam Filter?  

Most professional-grade – and, frankly, free – online email services provide some form of spam filtering. But not every program is the same.  

The right spam filter should be able to: 

  • Scan both inbound and outbound mail to account for internal compromises. 
  • Scan for indications of malware, ransomware, and phishing, not just one of the above.  
  • Ensure that your valid emails do get delivered. 
  • Properly and safely store your information. 
  • Offer scalable solutions at an affordable price.  

How does your current filter stack up? Here’s what you need to know about the junk mail capabilities of your current email provider: 

  • Gmail – Gmail is largely believed to have one of the best spam filters among publicly hosted email providers. With Gmail, messages to your inbox first pass throw a blocklist of malicious addresses from Gmail’s own database. Then, the same message passes through a content and link filter, followed by an in-house machine learning program aimed to help Google take a more proactive approach to security in the future.  
  • Outlook – By default, Outlook’s Junk Folder is set to No Automatic Filtering. Whether you use Outlook on its own or as part of a Microsoft 365 suite, it is highly encouraged that users go in and update your inbox’s Junk Folder to a more stringent level. You’ll also want to disable “trust my contacts” from the Safe Senders tab, as your contacts could also be hacked. These customizations can seriously improve Outlook’s junk folder success rate.  
  • Yahoo – Yahoo’s SpamGuard is a basic spam filter, but no less necessary to fending off cybercriminals. Like Outlook, Yahoo also offers some customizable choices that you should absolutely enable.  

Don’t Let Cybercrime Slip Through the Cracks 

Customizing the spam filter within your current email platform is a great place to start when it comes to protecting your inbox, but you shouldn’t stop there.  

While the filters provided by providers like Google and Microsoft are good, they are nowhere near perfect. If you’re serious about protecting your sensitive information – and you really, really should be – then a more advanced solution might just be for you.  

EMPIST offers comprehensive spam & virus filtering built to protect your data and your peace of mind. Rest easy knowing that you’ll receive access to regular quarantine reports, cost-effective integrations, and a first-line defense from viruses, phishing, and other potential threats.  

Learn more by visiting us online, here.