How do you Secure a Container?

What is a Container?

A container is a standard, standalone software unit that encapsulates code with its dependencies so that an application may operate rapidly and consistently in various computing environments. Containers are a type of virtualization for operating systems. All of the necessary executables, binary code, libraries, and configuration files are contained within a container. A single container can handle a small microservice to a larger application. Containers do not contain operating system images. As a result, they are more lightweight and portable, with less overhead. Container images are stored in containers. These images are layers of files rather than actual images, with the base image serving as the starting point for constructing derivative images. As a result, the base image is the most critical to secure.

What is Container Management, and How can it help you?

Container management is a method of automating container development, deployment, and scalability. Container management allows for the large-scale addition, replacement, and classification of containers. This is usually accomplished by analyzing and safeguarding all of the images that your team downloads and builds. To assign role-based assignments, automate policies, reduce human error, and discover vulnerabilities, private registries and metadata are employed.

Importance of Container Security

Containers provide some inherent security benefits, such as enhanced application isolation, but they also broaden a company’s danger landscape. Organizations may face increased security risks if they fail to understand and plan specific security procedures related to containers.

Container deployment in production environments has increased significantly, making containers a more desirable target for attackers. Additionally, a single vulnerable or exploited container could become a point of entry into a company’s infrastructure.

With the increase in traffic across the data center and the cloud, few security controls are in place to keep track of this major source of network traffic. As the conventional network security solutions do not guard against lateral threats, all of this emphasizes the significance of container security.

How to Secure a Container?

The Application Container Security Guide, issued by the National Institute of Standards and Technology (NIST), describes various essential techniques to secure containers. The following are some significant points from the NIST report:

  • To reduce attack surfaces, use the container-specific host OS: NIST recommends using the container-specific host operating systems. They are specially designed only to run containers with reduced features that help minimize attack surfaces.
  • Group containers based on purpose, sensitivity, and risk profile: Grouping of containers helps an organization make it difficult for the hacker to access one of the groups to extend the compromise to others.
  • Use vulnerability management and runtime security solutions: When it comes to containers, traditional vulnerability testing and management technologies often have blind spots, leading to erroneous reporting that everything is fine regarding container images, configuration settings, and others. Maintaining runtime security is an important aspect of container deployments and operations. Traditional perimeter-oriented tools, like Web Application Firewalls (WAFs), intrusion-prevention systems (IPS), were not explicitly designed for containers and cannot defend them properly.

Docker Container Security Best Practices

Docker, a market leader in containerization, offers a container platform for developing, managing, and securing applications. Customers can use Docker to deploy both traditional applications and the latest microservices from any location. You must ensure that you have enough protection, just as you would with any other container platform.

There are some best practices for Docker security:

  • To avoid malware, only use images from credible sources.
  • Reduce your attack surface by using thin, short-lived containers.
  • Limit SSH access by enabling troubleshooting without logging in.
  • Sign and Verify Docker Images.
  • Do not include sensitive data in Docker images.
  • Detect, fix and monitor open source vulnerabilities.

Kubernetes Container Security Best Practices

Kubernetes is a portable and scalable open-source platform for managing containerized workloads and services. While Kubernetes provides security capabilities, you’ll need a dedicated security solution to keep your cluster safe, as attacks on Kubernetes clusters have increased.

There are some best practices for Kubernetes security:

  • Ensure that Kubernetes is up to date: Kubernetes is a container orchestration system with over 2,000 contributors and is frequently updated. Vulnerabilities are being identified and patched more regularly. It’s important to keep updated on Kubernetes versions, particularly as the technology evolves.
  • Restrict SSH Access: Restriction of SSH access to your Kubernetes nodes is another simple and important security policy that should be implemented in your new cluster. You should not leave port 22 open on any node, but you may need to troubleshoot problems. You can use your cloud provider to set your nodes to block all access to port 22 except through your company’s VPN.
  • Establish Security Boundaries by using namespaces: Isolate components by creating different namespaces. When different workloads are deployed in separate namespaces, it becomes much easier to apply security rules.
  • Regular auditing and monitoring: Ensure that audit logs are enabled and should be monitored for abnormal or unwanted API requests, particularly for any authorization failures. Authorization failures indicate that an attacker is attempting to use stolen credentials. Managed Kubernetes providers, such as GKE, provide access to the data through their cloud console and may allow you to set up alerts for authorization failures.

AWS Container Security Best Practices

AWS understands the importance of containers in enabling developers to deploy applications more quickly and consistently. So, they offer a scalable, high-performance container orchestration, Amazon Elastic Container Service (ECS) and Amazon Kubernetes Service (EKS), that supports Docker containers.

There are some best practices for AWS container security:

  • Environment Tests: Perform environment tests with the help of tools such as Prowler to confirm that the environment is working as intended before deployment tackles the security threats. AWS shared responsibility model means that users should keep the environment secure, monitor container security, and regulate network access.
  • Unnecessary Privileges: Allowing unrestricted access or granting rights to the containers themselves increases the risk of security breaches. The more default access anything has, the greater the risk of a container being compromised. It also makes it more difficult to trace the entry point for a breach.
  • Focusing on Container: When it comes to securing the ecosystem, don’t make the mistake of focusing solely on the containers. The hosts that run the container management system are also important. Assess the security of all components, scan vulnerabilities regularly, monitor threats and keep the system up to date.

Microsoft Azure Container Security Best Practices

There are some best practices for Microsoft Azure container security:

  • Private Registry: Images from repositories are used to create containers. These repositories might be part of a public or private registry. The Docker Trusted Registry, which may be installed on-premises or in a virtual private cloud, is an example of a private registry. You can also use Azure Container Registration, which is a cloud-based private container registry service. Publicly available images might not be secured as images are made up of multiples software layers, each of which can be vulnerable. So, you should store and retrieve images from a private registry, such as Azure Container Registry or Docker Trusted Registry, to help reduce the threat of attacks.
  • Secure Credentials: Containers can be distributed across multiple Azure regions and clusters. As a result, credentials such as passwords or tokens are required for logins or API access must be kept secure. Only privileged users should have access to those containers while in transit or at rest. All credential secrets should be inspected, and developers should use emerging secret-management tools designed for container platforms.
  • Monitor and Scan Container images: Utilize solutions to analyze container images stored in a private registry for potential vulnerabilities. Azure Container Registry optionally integrates with Azure Security Center to scan all Linux images pushed to a registry. The integrated Qualys scanner in Azure Security Center detects image vulnerabilities, classifies them, and provides mitigation guidance.