5 Best Container Security Practices

Contrary to popular belief, containers have been around for many years, however, organizations have only just started to popularize them. Securing your containers is a critical process that can also be complicated.

This post takes you through some of the best container security practices that you can implement to avoid any issues. By the end, you’ll have a better idea about some of the key elements to consider to properly secure your containers.

Securing Images

One of the most important aspects to consider when it comes to container security is to secure your images. Since containers derive from images, the images must be secured from the start of the development process.

Developers can either create images themselves or get them from third-party sources. Generally speaking, images that come from third-party sources may present more security risks.Having said that, images that developers have created themselves can still come with a set of vulnerabilities. This is because images that are created by a developer still include third-party code.

So, developers must have a clear understanding of where the images have originated from. This involves going through lists of sources that are trusted and implementing systems that only allow for trustworthy images. This ensures that you prevent developers from using images that are more prone to security risks from the beginning.

Docker and Notary are examples of open source tools that can be used during this process. They enable their users to provide verification for the content being uploaded which gives organizations a clear indication of the authenticity of the images.

Strengthening Host Environment

One of the other critical features to consider is how strong your host environment is. Host environments are the platform that your images operate on. Therefore, you should make sure that the security of your host environment is tight to prevent breaches.

A common practice for developers to strengthen host environments is to get rid of native services that aren’t critical. This means that users can only gain entry to the host via containers which provide developers with a centralized control system. It also prevents the host from being exposed to the surface where attacks are more likely to happen.

The idea behind strengthening your host environment is to make sure that the entire platform that your images and containers are running on is secure. Organizations that focus only on their containers may find themselves at a higher risk of breaches as their system as a whole is weak.

Fixing Security Risks

When it comes to deploying software, it can be difficult for developers to locate vulnerabilities. This can lead to more security risks slipping through the net and causing issues down the line when they’re later detected.

During upstream projects, it can be tricky for organizations to have control of all the code that developers are using and creating. Therefore, it’s critical to have a system in place that provides you with information about the potential vulnerabilities of the projects.

It should also be noted that companies who are making a more drastic move to using containers will need to deploy more vulnerability scanning than they’re used to. Being able to scan large projects quickly and efficiently is critical to ensuring that your developers can work effectively without missing security risks.

You may need to consider upgrading your vulnerability scanning tools to ensure that they’re able to scan for security risks among formats with containers.

Deploying Container Security Tools

Introducing container security tools is vital for keeping your containers and images secure. Trying to manually look for vulnerabilities would be incredibly tedious. Therefore, it’s best to use tools as they can automatically scan for anomalies and notify you right away.

These tools also scan for vulnerabilities on a continuous basis which ensures that your developers and security teams don’t miss potential threats. They can then work more efficiently to remediate the problem before continuing with development.

Prior to using container security tools, you should ensure that your servers are up to standard in line with the benchmark set out by the CIS. Container security tools often compare the security of your containers with information from the CIS database and standards that they’ve set.

Consider Reducing Container Size

Companies nowadays seem to be struggling for ways to keep their containers secure. However, the whole idea of containers in the first place was to provide developers with a more secure platform to develop.

Originally, containers were created with the idea of being used more lightly rather than being relied on as heavily as they are today.

Containers can be highly beneficial for developers, however, if they’re being used as a server, you end up defeating the advantageous features. It’s common for developers to continuously add files and increase the capacity of containers whilst updating them infrequently.

This approach to using containers reduces their performance capabilities and increases the chances of security risks. Implementing large containers increases security risks and creates a larger area for hackers to attack your system.

Therefore, you should consider reducing the number of files that you add to your containers. This is especially the case for containers that are being frequently used. It’s also good practice to routinely update containers that you use all the time to get rid of files that are no longer needed.


Containers can be used to improve security and make it easier for developers to focus on developing code, rather than being stressed about security risks. However, containers are the most advantageous when they’re being used correctly and when the right security measures are being put in place.

If you’re finding that your containers are coming under a lot of threats and exposing your system to vulnerabilities, it’s time to take a step back and evaluate how your developers are using them.

Consider the methods in which containers are being deployed, as well as how often they’re being used, how images are being sourced, and how large the containers are.

Hopefully, the practices mentioned in this post have provided you with more insight into how you can secure your containers and use them effectively.