What Is Container Security? Complete Guide

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Container security is the combination of cybersecurity tools, strategies, and best practices that are used to protect container ecosystems and the applications and other components they house.

Containers are unique computing environments that lend many different advantages to users, but their design can also introduce new kinds of security vulnerabilities and challenges. With dedicated container security tools and processes, your organization can ensure that containers stay up and running and continue to protect the applications and data they host with minimal disruption.

10 Components of Container Security

When you’re first setting up containerized applications and infrastructure, it’s important to consider each component of the containerized environment through the lens of cybersecurity. The 10 components listed below not only cover the main components of containerized network architecture but also the container security tools that are most important for this type of network setup.

1. Container network security

A container network is an interconnected, typically virtualized network that is developed between an organization’s different containers. Examples of container networking and virtualization tools include VMWare NSX and HAProxy. Container networking tools help organizations manage communication, interoperability, and scalability while still maintaining control over how individual containers interact with each other.

2. Container runtime security

A container runtime is a type of software that runs containers on the host operating system(s). Examples of container runtime platforms include Docker Engine, containerd, and runC. Container runtime security tools help administrators manage policies, configuration drift and abnormal network traffic, attempted privilege escalations, user access controls, cross-container communications, and container monitoring and logging once a container is up and running.

3. Container registry security

A container registry is a storage repository or catalog for container images that can be pushed or pulled into your running containers through their connection to container orchestration platforms. Some common examples of container registries include Docker Hub, Azure Container Registry, and Amazon ECR. Container registry security tools help users manage image-level security, adjust user privileges, scan images for vulnerabilities, audit image libraries to identify outdated or problematic images, and mitigate supply chain risks.

4. Container orchestration security

A container orchestration tool is what automates and enables the quick deployment and scalability of containers. The best-known example of a container orchestration solution is Kubernetes. Tools that support container orchestration security help users maintain container isolation, manage third-party components, and harden both container runtimes and orchestration platforms while scaling up their container deployment activity.

5. Container image security

Container images are files that contain a microcosmic collection of what’s needed to set up a new container, including container runtimes, registries, configuration settings and specifications, the host operating system kernel, and other information about what can and can’t run on that container. Container image security solutions help users regularly scan image packages and dependencies for vulnerabilities; in many cases, container image security is managed by container registry security solutions.

6. Access controls and user privileges

Identity and access management (IAM) solutions are frequently used to designate specific user privileges in containerized applications and environments. Much of user access management can be handled manually or without tools, but especially as you begin to scale up your container network and differentiate how each container operates, it’s a good idea to invest in tools that support automated credentials and directory management.

7. Container-level segmentation

A number of container and workload segmentation tools are available to manage container isolation and limit lateral movement in cloud environments. These segmentation or microsegmentation tools help to manage zero trust and user access controls with identity verification, enforce application and workload-specific policies, and provide a consistently updated map of where applications live and how they’re being used.

8. Vulnerability scanning and management

Container vulnerability scanning frequently involves looking at the entire container image and then analyzing how workloads, runtimes, orchestration platforms, and other factors may make the overall image more vulnerable to security threats. Beyond simply scanning for vulnerabilities, many container security tools also help to automate the patching process.

9. Container monitoring and logging

Container monitoring and logging tools track the activities and behaviors of microservices, applications, and other components of a containerized environment, reporting any unusual behaviors to your organization’s security administrators. For best results, look for container monitoring tools with event and log correlation, code instrumentation, easy configurability, and compatibility with multiple data sources and types. Most container monitoring and logging tools are affordable, and many are open-source solutions.

10. Container encryption and secure storage

With container encryption, the entire container’s information and operations are hidden from plain sight rather than just individual files or datasets. Container-level encryption is a helpful way to balance secure storage and accessibility, because authorized users can decrypt the container and then access all relevant information in that container from there (though many organizations opt to include additional layers of file and data encryption). Container encryption solutions are best for protecting against backdoors, creating hidden containers, and securely managing cross-platform container security.

See the Top Container Security Solutions

Best Practices on How to Secure Containers

Securing containers requires a combination of traditional cybersecurity strategies and dedicated container security practices. Below, we’ve gathered some quick tips for how to secure your containerized environment:

  • Don’t neglect broader cloud and network security tools and strategies in your container security management efforts.
  • Stay up-to-date with patches and application upgrades across all containers and container components.
  • Take advantage of built-in, configurable security tools in container environments; many already have security capabilities that simply need to be set up.
  • Ensure your security teams have application-level visibility and regularly use threat monitoring, logging, and vulnerability scanning tools across each application and container.
  • Automate your security scans and other tooling wherever possible.
  • Use only vetted container images from trusted sources.
  • Set up access controls and usage policies that are specific to each application, platform, and container.
  • Regularly audit your containers, alongside your entire network.

Read more on this topic in our Container Security Best Practices Guide.

Benefits of Container Security

Containers make it possible to run granular network operations, and for teams that think strategically about container security, that freedom to customize extends to the cybersecurity tools they use and decisions they make. Learn about some of the specific benefits of container security below:

  • Security through segmentation and isolation: Containerized applications and business workflows are purposefully isolated from other containers; containers do a great job of enabling lightweight and efficient computing, and through their isolation, they also help to prevent the spread of security incidents from one application to another, essentially decreasing your organization’s attack surface.
  • Consistent builds, immutability, and secure scalability: Once initial container environments are set up for an organization, it becomes much easier to replicate that infrastructure and its security features as computing requirements grow or change. As long as your team establishes strong security tools and procedures from the start, those best practices will transfer to all future containers you build.
  • Strategic structure for DevSecOps teams: The tools and best practices associated with container security are optimally designed for DevSecOps. By implementing container security best practices, organizations can ensure developers, security teams, and operations teams all have a hand in and invest time in managing cybersecurity while developing and using containerized applications.
  • Container-specific user permissions: Containers operate like miniature networks, making it possible for network administrators to set up container-specific, clustered user permissions. User permissions and capabilities can be confined to specific applications and containers, which limits the possibility of user credentials being stolen and used in an unauthorized fashion across multiple containers.
  • Focused environments for continuous security monitoring: Containers are typically given dedicated tools and resources for continuous security monitoring. A focused approach to continuous security monitoring makes it easier to detect threats and anomalous behaviors before they spread to other parts of the network or worsen.
  • Configurability for compliance and security audits: Containers are highly configurable and customizable environments, which makes them ideal for complex policy and compliance management requirements. For example, if a specific policy or regulation only applies to one of your departments or projects, the appropriate security rules and settings can be applied solely to that container.
  • Simpler security process automation: A number of third-party plugins, extensions, and tools are available to automate security management for containers. Automated tooling options include registry scanners, compliance auditing tools, container firewalls, container workload and host monitoring tools, and alerts and notifications.
  • Efficient deployment and rollback: Because containers are both isolated and lightweight, it is easy to set them up and roll them back quickly. This is advantageous in many ways but particularly for cybersecurity because containers that have been impacted by a breach or other suspicious activity can quickly be rolled back to stop the spread to other containers.

Container Security Risks

Container infrastructure involves many different components that are simultaneously running independently and interconnectedly, so it’s no wonder there are several different weak spots for cybersecurity vulnerabilities to creep in, often without network administrators and security teams noticing. When working in a containerized environment, it’s important to be aware of the following security risks:

  • Limited visibility: The isolated and segmented nature of containers produces many positive cybersecurity effects, but it has one major cybersecurity drawback: limited visibility for your cybersecurity team. Unless your cybersecurity team uses purpose-built container security, threat monitoring, and dashboarding tools, it will be incredibly difficult for them to do quick security spot checks of your entire network since it’s divided into separate containers with different rules, permissions, and operations.
  • Container image vulnerabilities: Container images, especially those from untrusted or unfamiliar third-party sources, may be outdated, unpatched, and/or include malware, spyware, and various vulnerabilities that put your containerized environment at risk. There’s also the risk of image poisoning, or the act in which hackers use backdoors to bring malicious container images into your existing environment without user knowledge.
  • User error in container configuration: Even if just one container, application, orchestration platform, or other component of your network is misconfigured, new security vulnerabilities and issues can impact your containers; containerized components rely heavily on each other and can suffer major consequences if another component is misconfigured and left vulnerable.
  • Kernel vulnerabilities: Regardless of the hardware or software you use to build out your network, your operating system cannot run without a kernel. Both the host operating system and all hosted containers rely on this core kernel, so if an attack or vulnerability successfully reaches the kernel, it could then impact the rest of the containerized environment.
  • Orchestration platform vulnerabilities: Orchestration platforms have their own cybersecurity risks that can affect the containers they manage in a distributed environment. Orchestration-specific cybersecurity risks include outdated patches, API exposures, misconfigurations, and the general complexities that come with managing security for multiple microservices.
  • Inconsistent patching and retuning efforts: Containers and all of their components need to be regularly audited and updated in order to maintain security. Individual applications, container images, and container orchestration platforms can all introduce new vulnerabilities into the network if they are not regularly reviewed and patched as new issues are discovered and updates are delivered.
  • Loose user access privileges and policies: Containers make it possible for organizations to set up highly segmented user access controls and privileges, but many organizations do not take advantage of this capability. The loose approach most take to managing container access privileges can lead employees and attackers alike to manipulate containers and hosts through Docker APIs, escalate container privileges, leak data, or introduce unapproved container images.
  • Third-party exposure: In many cases, third parties have some kind of access to the applications you host in containers, or they may be the owners of applications, libraries, or dependencies that are running in your containers. It can be incredibly difficult to monitor and regulate third-party behavior in your organization’s containers without the proper tools and procedures in place.

Bottom Line: The Importance of Container Security

A growing number of businesses handle computing and daily operations in containerized environments. However, many businesses are not considering the breadth and depth of the container security tools and practices they need before getting started. Bad actors have picked up on this flaw in businesses’ security plans and are targeting containerized environments now more than ever before.

To truly protect the modern attack surface, it’s necessary to incorporate container-specific security tools and best practices into your cybersecurity strategy. Although containers already have some native security benefits, they also pose some additional risks, especially in the ways they limit your cybersecurity team’s ability to view the entire attack surface at a glance. Adding purpose-built container security to your cybersecurity efforts will give your team the peace of mind and support they need to manage vulnerabilities and threats in containerized environments.

Next: See the Top Cloud Workload Protection Platforms (CWPP)

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