Container Architecture for Security

From monolithic to hybrid architectures and beyond, part of ensuring that containerized applications remain secure is how they’re constructed. And while it’s common for DevOps teams to implement containers without considering how to protect them against compromise or ensure high availability, it often leads to a mix of cloud architectures and security concerns. We’ve discussed issues around different cloud and container architectures, like Kubernetes security, hybrid cloud set-ups with on-premise infrastructure, and securing containers in the multi-cloud.

In this article, we’ll examine the key needs of and design of container environment, including how containers are used, organized, and interconnected, in order to ensure security is built into the architecture itself.

What is Container Architecture (And Why Does it Matter for Security)?

A container architecture is what makes it possible to deliver software and all necessary dependencies into a single isolated unit, or container, which can run in any environment. In terms of security, that might include:

• Monolithic architectures, with components of applications packaged into a single container.
• Microservices architectures, with applications broken into smaller, coupled services running their own containers.
• Serverless architectures, in which containers are ephemeral, spun up as needed.
• Hybrid architectures, combining containers with bare metal infrastructure or virtual machines (VMs).
• Architectures using container orchestration, like Kubernetes, to manage container deployment, scaling, and networking

Container architectures come with their own security benefits and drawbacks, and securing each one has its own best practices. Further, most organizations use multiple container architectures, especially as they scale, or as they transition to cloud environments.

For example, monolithic architectures come with a simple attack surface, but if one part of the application is compromised, that compromise could spread throughout the entire application. 

Security Benefits and Drawbacks for Different Architectures

Container architectures are evolving with the tech and business needs of the organizations they serve, with increasing numbers of teams offloading infrastructure management in favor of serverless container management.

By 2027, more than 50% of container management deployments will be serverless, up from 25% in 2024.

That points to the increasing reliance on cloud-native technologies and the desire to simplify operational complexity. But with limited visibility into their ephemeral nature, the move presents newfound security challenges. Ultimately, no single architecture has a monopoly on security — trade-offs reign supreme. Here are the benefits and drawbacks of the most popular architecture types.

Monolithic Architectures

Monolithic architectures can be tempting. They’re simple to deploy and come with unified security controls, meaning teams can apply security directly to policies in a single container to manage access and configure security settings. And they’re also less vulnerable to attack, with fewer vulnerabilities to be exploited compared to apps with more surface areas, like microservice architectures.

Monolithic architectures aren’t without drawbacks. They limit fault isolation with their single-container approach. With one attack, the entire application might fail. That leads to more difficult scaling and patching issues, too. A single patch can require the entire app to be redeployed, for example. And because there’s a single container for the entire app, there will necessarily be a single set of security controls for that app, giving teams less granular control over components.

Microservices Architectures

Microservice architectures contrast with monolithic ones in that each service is contained within its own container, so a breach in one service doesn’t necessarily impact the others. That makes for easier patching and updating and granular access control teams won’t get with monolithic architectures.

However, microservice architectures don’t just solve all the issues monolithic architectures introduce. They come with their own downsides. The more complex attack surface means more monitoring is necessary. And there are inter-container communication risks, as interactions between containers become crucial. Unsecured communication channels can lead to man-in-the-middle attacks, for instance. There’s also a greater risk of misconfigurations in this architecture since teams will need to manage security at the individual service level.

Serverless Architectures

In serverless architectures, ephemerality reduces the attack window, with temporary containers disappearing and reducing the time an attacker can exploit their vulnerabilities. They’re also running in cloud environments, where cloud providers handle some security tasks. They’ll patch the underlying infrastructure, for example, potentially improving the security posture of these kinds of deployments. And they’ll help automatically scale and isolate functions, making it harder for a compromised function to impact others.

Serverless architectures offer less visibility and control over the serverless environment for teams. And their dynamic, short-lived nature means that threat detection can be more difficult. Further, serverless architectures can have “cold start” vulnerabilities as malicious code runs before functions fully initialize, making it possible to bypass security controls.

Hybrid Architectures

Hybrid architectures come with “the best of both worlds” security benefits alongside “the worst of both worlds” challenges. They allow organizations to run sensitive workloads in more secure environments, like VMs or bare metal, while separating less sensitive workloads in the cloud. And they maintain isolation between legacy systems and newer containerized workloads, making for more security as environments are separated.

But managing different types of infrastructure is difficult, as each requires its own policies and controls. Integrating comes with its own risks, including competing security models. Finally, hybrid environments can be resource-intensive and difficult to monitor comprehensively, leading to extra work with more gaps.

Container Orchestration Architectures

Orchestrators like Kubernetes handle security tasks like scaling, which reduces the complexity inherent in managing containers. And it allows for granular control over the network environment, handling communication between containers and reducing lateral movement attacks. Orchestrators also allow for Role-Based Access Control (RBAC), which allows for tightly controlled access to resources.

With those benefits come drawbacks like an increased attack surface, as they add a management layer (i.e., the API server) that needs its own security. The added complexity doesn’t stop there; handling multiple containers always increases the risk that misconfigurations emerge, like overly permissive roles or insecure network policies. And orchestrators centralize management of containers — they necessarily offer up a centralized attack vector, too. If the orchestrator is compromised, it could allow an attacker to gain control over the entire container environment.

Best Security Practices in Different Container Architectures

When it comes to securing containerized environments, the choice of architecture plays a critical role in determining security outcomes. But no matter which architectures already make up the environment, some best practices can help secure each.

Container Architecture Type	Key Security Challenges	Best Security Practices
Monolithic Architectures	A single container increases the risk of widespread compromise.	Minimize container size Use trusted, minimal base images Isolate sensitive services and use encrypted communication for external services
Microservices Architectures	Multiple services present an increased attack surface.	Implement service mesh for secure communication Use network segmentation and RBAC for pod access Ensure that services run with least privilege
Serverless Architectures	Ephemerality makes continuous monitoring and runtime protection difficult.	Implement runtime protection to detect anomalies Use immutable infrastructure for functions Monitor short-lived containers in real time
Hybrid Architectures	It’s difficult to manage security across both containerized and legacy environments.	Use unified security policies for both containers and legacy systems Automate vulnerability scanning and patching across environments Maintain consistent monitoring
Kubernetes Orchestration	Orchestrator misconfigurations can expose the system to attacks.	Apply RBAC, network policies, and secure pod communication Regularly audit and patch Kubernetes clusters Monitor and secure the orchestrator itself

However, securing containers is not just about selecting a single architecture — many organizations operate with multiple container architectures in play. Whether teams are using a monolithic design, microservices, serverless, a hybrid model, or a Kubernetes orchestration, making sure that your container architecture remains secure requires a combination of architectural decisions along with these best practices. 

Key Considerations for Secure Container Architecture

Architecture Selection

The security considerations for a monolithic architecture differ from a microservices-based architecture. In a monolithic system, teams will focus on securing the overall container image and reducing the attack surface by minimizing the number of services inside the container. With microservices, security will focus more on service-to-service communication for more secure authentication and securing inter-container communication.

For serverless or ephemeral containers, the security focus shifts to runtime protection and making sure that short-lived containers don’t become vectors for attack due to improper initialization or insecure defaults.

Hybrid Environments

And yet very few teams are starting from scratch, making the decision about architecture from the perspective of security or with a plan to use just one architecture. Organizations use a combination of architectures, such as Kubernetes-based microservices, alongside legacy monolithic containers or VMs. Securing these hybrid architectures means their focus will inevitably be on integrated security policies that apply consistently across different infrastructures and environments.

Orchestration and Automation

Kubernetes and other orchestration tools play a foundational role in security, but they also introduce their own challenges. Misconfigurations in orchestration tools can expose the system to security vulnerabilities, so these tools will spur teams to adopt best practices around RBAC (Role-Based Access Control), secure pod communication, and automated patch management.

Security at Every Layer

In the end, security should be applied not only to the containers themselves but also to the container orchestration layer, the host system, and the underlying cloud or on-premises infrastructure. This ensures end-to-end security from image creation to deployment. But what does that look like?

A Holistic Guide to Securing Container Architectures

When considering container architecture security, it’s important to understand that security isn’t just about choosing the right architecture; it’s about how to apply security principles to the architecture as a whole, whether it’s monolithic, serverless, or hybrid. The reality is that all architectures, especially in combination, require a comprehensive, layered security strategy that spans the entire container lifecycle — from development to deployment and runtime.

That means a container architecture security strategy typically includes these components.  

Security at Every Layer

In any containerized environment, securing the container images, host operating system, networking, and orchestration layer is key to a unified security approach. For instance, securing a microservices architecture doesn’t only involve protecting each container but also securing communication between those containers, as well as between the container and external systems.

It also includes image security. Whether teams are using monolithic containers or a microservices architecture, they’ll need to build containers with trusted base images and scan them for vulnerabilities before deployment.

And it requires orchestration security. Tools like Kubernetes offer scalability and flexibility, but they also introduce configuration risks. Proper orchestration security means that RBAC, network policies, and secure pod-to-pod communication are enforced across the environment.

Integrated Security Policies

Today’s typical hybrid architecture, which may use both containerized services and traditional workloads (e.g., virtual machines), requires unified security policies that cover both environments. Containers might have more dynamic behaviors, but the security policies for managing both environments should be consistent to protect the entire architecture.

Integrated policies should address everything from access control to patch management so that vulnerabilities in containers or legacy systems do not create gaps that attackers can exploit.

Continuous Monitoring and Runtime Protection

Container architectures are all defined by their use of ephemeral units of compute, and especially in microservices or serverless environments, multiple containers can be spun up and torn down frequently. Anomalies, unauthorized activity, and potential vulnerabilities must be detected in real time to subvert lateral movement or escalation.

Runtime protection should also be architecture-agnostic. Whether teams are managing serverless containers that are ephemeral or Kubernetes-managed containers that are persistent, runtime security tools offer continuous monitoring for threats and stringent access controls.

Immutability and Automation

Immutability is a principle that strengthens container architecture security. Whether teams are deploying a monolithic container or running microservices, they’ll create immutable containers that cannot be altered post-deployment, reducing the risk of drift or unpatched vulnerabilities after deployment.

Further, automated CI/CD pipelines can integrate with security tools for continuous scanning and validation to ensure that no vulnerabilities or misconfigurations make their way into production containers. By embedding security into the build pipeline, it becomes part of the architecture itself rather than an afterthought.

Scalability and Resilience

Secure architectures, no matter their style, help systems remain available and resilient, even in the face of security incidents. For microservices and serverless architectures, the ability to quickly scale, isolate compromised services, and maintain operational continuity is key.

In Kubernetes, for example, teams might design for resilience by ensuring that clusters are configured to automatically handle failover and scale based on demand, while also making sure that each component (e.g., pods, services) is properly isolated and protected.

Consistency Across Environments

One of the biggest advantages of containerized environments is their ability to work across different infrastructures. But consistent security policies across environments are another story. Standardize security practices and configurations across the organization and across the software development lifecycle. 

It’s not enough to simply choose an architecture — and most of the time, it’s not entirely possible. Hybrid architectures are here to stay. But teams must also adopt security best practices that secure containers, orchestration tools, images, and communications across their entire infrastructure. Whether it’s through network segmentation, runtime monitoring, or vulnerability scanning, the goal is to implement security in a way that aligns with the unique requirements of your containerized architecture and keeping systems agile, scalable, and resilient.

Future Trends in Container Architecture

As more companies adopt cloud-native technologies, they contain architectures that incorporate more cloud workloads and microservices. In the future, they’ll incorporate other new technologies, too.

1. AI uses container data: It’s likely in the near term that, as AI and machine learning workflows become more common, containers will be used to feed models and data pipelines. This trend enables organizations to deploy AI solutions faster and more efficiently. 
2. Hybrid and multi-cloud strategies reign: Enterprises will increasingly look to avoid vendor lock-in and optimize their cloud investments by using multiple services depending on workload and increasingly normalizing hybrid environments.
3. Edge computing will impact containerization: Containers are ideal for edge deployments because of their portability and lightweight nature. As edge applications become more prevalent, containers will enable them to run effectively while also integrating with cloud services. 
4. Service mesh integrations are rising: They will provide dedicated infrastructure layers for handling service-to-service communication and make it easier to manage complex microservices architectures.
5. Serverless containers will dominate the landscape: As serverless containers become more popular, they’ll increasingly help teams simplify deployment and scaling, allowing developers to focus on their code.
6. Standardization and open-source collaboration remain strong trends in containerization: Open standards and open-source projects ensure interoperability, foster innovation, and avoid fragmentation in the container ecosystem. As hybrid architectures expand even more, expect the trend to continue.

Upwind Safeguards Container Workloads in any Architecture

Upwind’s cloud-native application protection platform (CNAPP) is designed to protect container architectures against attack, from monitoring for anomalous activity across multiple hybrid and multi-cloud environments to giving security teams the tools they need when they need them to protect the containerized ecosystem. This includes:

• Detection of anomalous behaviors and response powers in real-time for ephemeral workloads
• Enforcing policies at the container level, including access control, networking, and configuration.
• Continuous vulnerability scanning and remediation, from container images to host systems or orchestration layers.

To learn more about how Upwind secures container architectures and get advice on best practices, schedule a demo. 

Frequently Asked Questions 

What are the essential security layers in container architecture? 

Securing container architectures requires addressing multiple layers for comprehensive protection, safeguarding the layers themselves along with the overarching architecture. The essential security layers in container architecture include:

• Host system protection
• Container image security
• Runtime security
• Orchestration layer security
• Network security
• Secrets management
• CI/CD security

Each layer plays its own role in defending the containerized environment from attacks. While dedicated CNAPPs bring together every layer, they don’t all offer deep solutions for each (i.e., they can offer visibility into secret exposures across orchestrators but don’t function as secrets management tools).

How do you design secure container environments? 

To design a secure container environment, consider implementing security at every level and foregrounding the following protections for containers themselves:

• Using trusted, minimal base images and scanning them for vulnerabilities.
• Enforcing least privilege access and role-based access control (RBAC).
• Securing communication with network segmentation and encryption.
• Continuously monitoring runtime behaviors for anomalies.
• Protecting secrets with secure management tools.
• Automating security checks in CI/CD pipelines and during deployment.

What role does orchestration play in security architecture? 

Container orchestration plays a vital role in container security architecture. How? It’s the basis for how containers communicate with one another and what the attack surface looks like. Roles it plays include:

• Enforcing Security Policies: Orchestration platforms like Kubernetes enforce security policies such as role-based access control (RBAC), network segmentation, and pod security policies.
• Centralized Management: It provides a centralized platform for managing security configurations across multiple containers.
• Runtime Security: Orchestration tools help monitor container behavior during runtime.
• Automating Updates and Patches: Orchestration platforms automate the deployment of security updates and patches across containerized environments.

How do you protect container runtime environments? 

Protecting runtimes means monitoring and securing containers while they execute. Key practices are:

• Runtime Monitoring: Continuously monitoring container activities for anomalous behavior, privilege escalation, and unauthorized access.
• Access Control: Enforcing strict least privilege access and using role-based access control (RBAC) to limit container permissions.
• Network Segmentation: Isolating containers using network policies.
• Runtime Integrity Checks: Using tools to detect and prevent unauthorized changes to container configurations or files while they run.
• Security Automation: Implementing automated runtime protection tools to block attacks and respond to threats in real time.

Runtime-powered CNAPPs like Upwind align with all these practices to support containerized environments.