Benefits & Limitations of Docker Security Scanning

Using docker image security scanning is a vital process that helps with improving your defense against attacks or insecure code via container images. Docker security should always include scanning procedures as a standard part of the development process.

This post covers more information about docker security scanning, as well as the benefits and limitations that you can expect to encounter. By the end, you’ll be feeling more assured about using docker security scans and have a realistic expectation about the results that it can provide.

How Docker Security Scans Work

Docker involves a container image as a file that provides information about what processes and data should be used in a specific container when it’s executed. Developers can use docker images as a guideline for safeguarding applications and ensuring that they can run efficiently within a container.

A Dockerfile must be created before using a Docker image. This involves a file of plain text that includes details about the elements that should be included within your container image. For the most part, Docker base images will be used by a Dockerfile to alter the base image. This results in additional components or processes being added to base images.

You can create an image after you have a finished Dockerfile. After this, you can upload the image to a registry for containers that you can easily download when it comes to times when you want a container to be run.

Image Scanning

Image scanning involves a process that enables developers to discover vulnerabilities inside docker image files. This helps organizations to fix issues from causing larger issues at a later date.

This type of scanning enables the tool to go through all of the elements within a container image file and notify you if there are any vulnerabilities. If there are vulnerabilities picked up within files, the tool should alert you of a security risk.

As a result, developers are provided with a clear understanding of what areas of their files are vulnerable. They can then systematically work through the vulnerabilities and fix them one by one until the Docker file is secure.

Limitations of Docker Security Scanning

After reading through some of the main benefits of Docker security scanning, you may be wondering whether this type of scan comes with any limitations. There are several Docker security scan limitations that you should be aware of to keep your expectations in check before using them.

Docker security scans should be used as a tool to provide developers with a better idea about vulnerabilities within Docker files. It shouldn’t be used as a way to provide total coverage against security risks.

Tools that are used for scanning Docker images typically check through public databases. This is effective when it comes to giving you accurate reports on known vulnerabilities. However, it still leaves you exposed to vulnerabilities that aren’t publicly known.

Therefore, developers should use Docker image scanning tools as a guideline to help keep track of known vulnerabilities while still being aware that there could be unknown security risks present.

Sharing resources among containers can be an effective way for developers to work together more efficiently. However, during the process of sharing resources, security risks could become present.

This is largely due to configurations for sharing resources being insecure. Docker image scanning tools aren’t able to discover these issues due to how they haven’t happened within container images.

If your developers are running containers by root, Docker image scanning tools are ineffective at discovering vulnerabilities. This is also the case when it comes to Kubernetes configurations that are insecure.

In this case, it’s best to use other tools to detect vulnerabilities among your configurations to ensure that they remain secure.

Docker image scanning tools work by finding certain components are within a Docker image. These components are already known publicly and can be effective at finding a range of security risks.

Having said that, Docker image scanners can’t find all vulnerabilities. This can become a larger issue when it comes to developers using open-source elements within code. Open-source components can help developers work more efficiently, but it can prove troublesome when it comes to detecting vulnerabilities that they may contain.

Therefore, you may want to consider implementing other types of scans to find vulnerabilities within open-source elements that are being used in your Docker images. There are tools that are great for finding where the open-source or 3rd-party code originates from.

This can provide developers with a clearer indication of where the 3rd-party code originates from. As a result, they can take the necessary measures to find vulnerabilities and fix them before continuing with development.

Improving Container Security

Developers can take steps to ensure that their containers remain as secure as possible. One of the main elements to ensuring this involves selecting the correct base images from the beginning. Be sure that your developers are selecting base images from sources that can be trusted.

Scanning images is a process that should be completed throughout the initial development stages as well as throughout the production and execution stages. This helps to keep your images as secure as possible at all development stages.

Developers may also want to consider rebuilding images after receiving results from Docker image scans. This is especially the case if there are a lot of vulnerabilities showing up. It may be worth starting fresh instead of spending time and resources on trying to fix so many issues.

Conclusion

Developers need to understand that Docker security scanning shouldn’t be the only type of container security scan being carried out. The most effective way to use Docker security scanning is to utilize it as one part of the security process.

This enables developers to keep realistic expectations about the results that can come from running Docker security scans. Hopefully, the details throughout our post have proven to be useful for understanding more about the pros and cons of using Docker security scanning tools.