Serverless security in system design

Serverless computing is a model in cloud-native in which developers can build applications and services without having to manage the underlying infrastructure on which these applications are placed. This does not mean servers have vanished in thin air; the developer is no longer accountable for server management. Combining cloud services and Function as a Service (FAAS) removes the requirement to manage and secure the hardware and virtual machines. Although serverless technology makes software development efficient, serverless apps are exposed to the same threats as traditional apps. Thus, developers need to adopt certain best practices because they are still accountable for security in the cloud.

Serverless security in system design

Old-school applications are usually protected with security infrastructure and network security tools. For example, firewalls inspect traffic, and intrusion detection systems pinpoint malicious activity or utilize runtime application self-protection (RASP). With serverless computing, we acquire flexibility and scalability and eliminate the chaos of securing our servers. If we effectively outsource all the responsibilities of managing and protecting our servers, we are reducing many costs associated with these tasks.

Benefits of serverless security

Serverless security brings several security benefits to the table:

• Exposed OS dependencies: Serverless architecture eliminates the need to patch our servers. It checks the spread of malware from one infected server to a healthy one and eliminates the problem brought about by HeartbleedA malicious bug that can read a system's memory..

• Denial of service (DoS): Since serverless is a pay-as-you-go service, in case of increased network traffic, a common occurrence in DoS attacks, where our server autoscales to accommodate increased network requests, we can design our systems to cater to upscaling. With fluctuating traffic, our server can increase or decrease in size to cater to changing traffic requirements, but remember, we still have to pay.

• Compromised servers: Serverless architecture provides statelessness, which means any compromised server does not survive long. Thus, this requires attackers to make more efforts—attackers have to make frequent attacks, risking being detected and reducing their odds of succeeding.

Security impediments in serverless computing

Several challenges are encountered when implementing serverless security:

• Data storage and privacy: Like traditional systems, serverless systems are not immune to data breaches and unauthorized access. Thus, data encryption, whether for data at rest or in transit, can not be compromised. Moreover, companies must effectively utilize key storage services like AWS Key Management Service or Azure Key Vault to enhance security measures.

• Function security: Serverless architecture’s dynamic nature exposes systems to code injections. Input validation and sanitization are required to prevent malicious code from being inserted into a system. Furthermore, this does not invalidate the need for strong monitoring and detection systems.

• Authentication and authorization: Serverless apps require adequate access controls because, if carelessly overlooked, they can grant unauthorized access to hackers. However, role-based access control (RBAC) ensures that only entities with the necessary permissions can access functions and data. Identity and Access Management (IAM) is a cherry on top—an added layer of security. It also gives the managing party granular control over managing user access.

Best practices

To make our app bullet-proof from malicious attacks and unwanted activity, we can adopt the following practices

• Principle of least privilege: This principle leverages the concept of giving the bare minimum. Any entity should be granted only the necessary permissions to complete its task. Companies can shield themselves from unwanted malicious activity by clinging to this principle.

• Secure deployment: Many security risks are carelessly ignored during the deployment phase. Thus, it is necessary to use security checks in automated deployment pipelines. For example, hypothetically speaking, Sam, a senior DevOps engineer, uses Jenkins to automate his company’s deployment process. In doing so, another senior developer, Annabelle, advises using Checkmarxhttps://checkmarx.com/ for dynamic application security testing. This is just one simple example.
  Moreover, utilizing Infrastructure as Code (IaC) ensures consistent and secure deployment. Lastly, security tools compatible with serverless security can detect security vulnerabilities. These security vulnerabilities might look like an amateur cloud engineer misconfiguring an AWS Lambda function.

• Monitoring and logging: As serverless computing leverages auto-scaling to accommodate fluctuating workloads, system design engineers must detect anomalies in the ever-changing system. Monitoring services can be incorporated with serverless systems.

• Other specifications: Some security specifications are unique to serverless security because of the nature of the system. For example, serverless systems enter a state called the cold stateInitialization of a function after staying idle., which necessitates keeping a hawk’s eye on the system’s activity to prevent the inclusion of vulnerabilities. Container reuse can be impersonated as a snake in disguise because it remembers data from the previous execution. Thus, in such a case, containers need to be used with stealth and isolation.

Conclusion

To wrap things up, in system design, serverless computing comes with many benefits as compared to traditional old-school applications in terms of implementing security and achieving scalability and efficiency. But we still need to keep certain risks in mind before we can implement security on serverless apps in the best possible way.