9 Best Practices for Securing Microservices | Complete Security

The microservices architecture provides flexibility, scalability, and the ability to modify, add, or remove software components without affecting other parts of the application.

Along with shorter software development cycles, smaller teams, and flexible programming language options, it allows you to scale or troubleshoot certain functions or services without interfering with other components.

In general, microservices allow you to divide large monogamous applications into separate, independently deployable services. However, these small independent services increase the number of components, hence the complexity and difficulty of securing them.

Typically, a typical microservices deployment will include hardware, service or application, communication, cloud, virtualization, and orchestration layers. Each of them has specific security requirements, controls and challenges.

Security challenges associated with microservices

Microservices are typically widely distributed systems with complex access rules, more traffic to monitor, and a larger attack surface. Additionally, most cloud microservices run on cloud environments, which also have varying configurations and security controls.

Due to the large number of APIs, ports, and components exposed , traditional firewalls may not provide adequate security. These issues make microservice deployments more vulnerable to various cyber threats such as man-in-the-middle, injection attacks, cross-site scripting, DDoS, and others.

Network security is another challenge with microservices. In particular, identity and access control take on a new level of complexity. Other vulnerabilities include insecure code and vulnerabilities in service discovery systems.

Although securing microservices is more difficult than monolithic applications, you can effectively protect them by establishing good policy and following best practices.

Ideally, the architecture requires a distributed approach which should cover all the different components.

Typical areas to be treated include

• Protect applications, microservices and users
• Secure identity and access management
• Protect data
• Improve the security of service-to-service communications
• Monitoring of microservices and security systems

Best practices for securing microservices

One of the best strategies is to use a combination of best practices, tools, and controls to protect the entire ecosystem. The actual approach may differ depending on the type of service, applications, users, environment, and other factors.

If you decide to use microservices, you need to make sure that you meet all Complete security requests for services, connections, and data.

Now let's take a look at some effective microservice security practices.

# 1. Build security from the start 👮

Build security into the development lifecycle. Ideally, build security  into the development and deployment of microservices from the start. Approaching security this way is a simple, effective, and cheaper approach than waiting to add it when software development is nearing completion.

# 2. Use the defense-in-depth mechanism

Defense in Depth (DiP) is a technique where you apply multiple layers of security to your services and data. This practice makes it more difficult for attackers to penetrate through multiple layers, thus providing enhanced security for your services and data.

Unlike perimeter security solutions such as firewalls, the concept of defense in depth is different. It relies on a combination of tools such as anti-virus, firewall, patch management, anti-spam software and others to provide multiple layers of security distributed throughout the system.

With this approach, you must first identify sensitive services, after which you apply the appropriate layers of security around them.

# 3. Deploy container-level security

Most often, microservices are based on Container technology. As such, securing containers, both internally and externally, is a way to reduce the attack surface and the risks. Ideally, aiming for the principle of least privilege security is good practice and requires a combination of strategies including, but not limited to;

• Limitation of authorization to the minimum required
• Avoid running services and anything else using sudoor privileged accounts.
• Limit or control the access and consumption of available resources. For example, limiting access to operating system resources by containers helps prevent data theft or compromise.
• Do not store secrets on the container disk.
• Use appropriate rules to isolate access to resources.

It is also essential to ensure that container images do not present any vulnerabilities or security issues. Regular analysis of container security and vulnerability will help identify risks.

Typical image scanning tools include Clear , Anchor  , and more.

# 4. Deploy multi-factor authentication 🔒

Enabling multi-factor authentication improves front-end security.

Accessing users will be required to provide their username and password in addition to some other form of verification, such as a code sent to their phone or a specified email address. The technique makes it more difficult for attackers, who can use stolen or hacked credentials, to access microservices because they will not have the means to provide the second authentication.

# 5. Use user identity and access tokens

In deploying microservices, a large number of applications and services will require secure authorization and access control. An authorization framework such as OAuth 2.0 and OpenID allows you to securely process tokens, thereby protecting your microservices. Therefore, it allows third-party applications to access other services or user data.

In a typical deployment, the main application will prompt the user to authorize the third-party service. By accepting this, the application generates an access token for the session.

In particular, OAuth is one of the most effective strategies for user identity and access control. While there are several other authorization protocols available and you can create your own as well, it is recommended that you use OAuth  since it is more standard, stable, and widely accepted.

# 6. Create an API gateway

Typically, microservices are made up of multiple components spread across different networks and accessed from a wide variety of systems and clients. Exposing microservices increases vulnerabilities and security risks. One way to protect them is to create a single, secure point of entry that helps you centralize all access from external systems and clients.

To do this, deploy an API gateway to filter all incoming requests for security concerns before routing them to the appropriate microservices. The API gateway sits between client applications and microservices. It then limits the exposure of microservices while providing additional request handling functions such as authentication, SSL termination, protocol translation, monitoring, request routing, caching, and more.

With this approach, the API Gateway routes all external services to microservices while also supporting the principle of defense-in-depth security.

# 7.Profile API according to the deployment area

Enforce role-based restrictions making sure users only have access to the APIs and services they need. Since most malware often exposes a service to more people, limiting access to only authorized users reduces the risk. One technique for reducing exposure is to label APIs based on the users who should have access to them. In general, APIs can be;

• Ethernet API - For services exposed to the external world outside the data center.
• Enterprise Zone APIs - these are intended for internal private traffic
• DMZ API - to manage traffic from the Internet
• Hybrid Zone API - for data center deployments

# 8. Secure service-to-service communications

Effective practices involve authenticating and authorizing requests when two microservices communicate.

In general, there are three main techniques you can use to secure inter-departmental communications. Here are the Trust the Network , JSON Web Token ( JWT), and Mutual Transport Layer Security ( mTLS , or Mutual TLS ).

Of the three, the most popular is mTLS. In this approach, each microservice must carry a public / private key pair. The client microservice then uses the key pair to authenticate with the receiving microservice through mTLS.

During authentication, each microservice generates a certificate. Then each microservice will use the other's certificate to authenticate.

While TLS ensures the integrity and confidentiality of data in transit, it also allows the customer to identify a microservice. The client microservice usually knows the other microservice. However, because TLS is one-way, a receiving microservice cannot verify the client microservice, and attackers can exploit this flaw. On the other hand, mTLS provides a means by which each of the microservices can identify the other.

# 9. Throughput limit 🚏 customer traffic

Limiting external traffic prevents problems such as denial of service (DoS) attacks as well as cases where certain clients consume most of the application's bandwidth. One approach is to apply various rules to monitor and control the rate of traffic sent or received from a client based on IP address, time, etc.

Configure your services to slow down if they detect multiple failed connection attempts to your APIs or any other suspicious activity.