What Do You Know About Blocklisting?

Multicolored Lego blocks

Maintaining effective cybersecurity measures is an ongoing endeavor for every organization. The best cybersecurity programs use a variety of tools and methods to keep bad actors out while supporting the efficiency and productivity of legitimate users. Allowlisting and blocklisting are both key tools that can be used to determine which applications are safe and which are not. But do you know what they are and how to use them effectively?  

In this post, we’ll take a look at how these two approaches work, how they differ, and what you should consider as you weave them into your cybersecurity strategy. 

Blocklisting vs Allowlisting: What’s the Difference? 

Application blocklisting and allowlisting operate as two sides of the same coin. Blocklisting prevents known malicious applications from running on your network, and allowlisting maintains a list of applications known to be safe, allowing only those on the list to run. 

How Does Blocklisting Work?

You can think of blocklisting as a bouncer that keeps out known undesirables. Essentially, a blocklist identifies and bans known threats, including specific applications, IP addresses, or email addresses that are associated with malicious activity. Any entity that is not on the list is granted access. Blocklisting is often used for spam filtering, anti-malware, and phishing attempts.

The drawback, of course, is that threats are constantly evolving. According to the AV-Test Institute, 450,000 new malicious programs are identified every single day. It’s not possible to keep up with the entire list, and we can’t know what new threats are coming until they happen. Ultimately, this means blocklisting can’t be 100% effective out keeping at the bad guys. 

How Does Allowlisting Work?

Allowlisting is the opposite of blocklisting. It’s the person checking invitations at an exclusive party: only those on the list get in. As a result, it is much more restrictive than blocklisting, and it’s more effective at keeping out unknown threats. Allowlisting is often used for devices dedicated to specific purposes, such as ATM machines or smart meters. It may also be used to monitor files, create an application inventory, and identify malware. 

The challenge of allowlisting is ensuring that you have every application your organization needs on the approved list. If you don’t, employees will have to submit requests to IT, which slows down productivity and hampers efficiency. In addition, initial setup may be time-consuming and complex. 

4 Considerations for Effective Implementation

Both blocklisting and allowlisting can play critical roles in a robust security strategy. One isn’t necessarily better than the other; they just have different uses. To decide when to use which strategy, you’ll need to know the unique needs and risks of your environment and determine which approach will deliver the best results. 

Here are four things to consider as you evaluate your needs:

  • Know your organization’s areas of risk. In most cases, allowlisting and blocklisting can and should be used in combination to provide the greatest security. Take a look at the risks for various parts of your network and processes, and determine which approach would provide the greatest security while still empowering employees to work efficiently and access what they need.
  • Keep lists updated. As new threats emerge, you will need to update your blocklist to prevent malicious files and applications. This is an ongoing endeavor that can be time-consuming, but it’s worth the effort to keep out known, destructive attacks.

    Allowlists will also need to be updated to maintain optimal protection. The National Institute of Standards and Technology (NIST) offers guidance on how to best implement allowlisting for your organization. 
  • Monitor activity to identify and respond to unauthorized access attempts. Use an access monitoring tool to log user activity and track access to sensitive data. Most tools will categorize activities, send alerts when suspicious activity occurs, and create visual reports so you can track metrics at a glance.
  • Educate your team about cybersecurity best practices. In addition to taking proactive actions like allowlisting and blocklisting (and many others), organizations should also train team members to follow security policies and best practices. This includes using strong passwords, recognizing phishing and scam attempts, not sharing credentials, and not clicking on unknown links. 

System Security Starts with the Right Plan

It takes a village to maintain an effective cybersecurity strategy. In the ongoing battle against cyberattacks, you will need to implement both offensive and defensive protocols to recognize and prevent security incidents.

At CyberFOX, we specialize in helping you put the right tools in place so you can sleep better at night. Contact us today to learn more about strengthening your security!

Get the latest insights delivered to your inbox

Subscribe to identity and access management news and resources from industry experts.