Top 5 Serverless Security Practices to Implement for Your Business Application

Serverless Security applications enable your business to give personalized, always-available digital customer experiences. 

They optimize development costs (letting you pay for the actual amounts of resources used rather than pre-purchase them) and ensure your software’s scalability. 

They also empower your DevOps teams to focus on writing high-quality code and solving business problems without worrying about architecture. The result? Increased customer satisfaction and product differentiation.

However, serverless platforms carry unique security risks that you and your DevOps teams should know and avoid.

Implement these five top serverless security practices to protect your business applications. 

1. Don’t depend on web firewall applications alone for protection.

Application layer firewalls can only assess HTTP(s) traffic. This means that they can only safeguard API-gateway-triggered functions. They cannot protect you from other event trigger types and sources, such as:

• Notifications, such as the internet of things (IoT), email, and SMS
• Database changes in Azure CosmosDB, AWS DynamoDB, and others
• Cloud storage events, e.g., Google Cloud Storage, Azure Blob storage, AWS S3
• Code adjustments stored in repositories such as AWS CodeCommit.

Web application firewalls (WAF) are crucial. However, they can leave you with several security loopholes. They must not be your sole line of defense when protecting serverless platforms and applications. 

Leverage robust serverless security tools along with WAF protection. They can automate your cyber defense and risk mitigation efforts and expose potential vulnerabilities. This makes it easy for your DevOps team to deploy and manage code safely, among others.

2. Implement the principle of least privilege.

You typically do not deploy serverless functions in isolation. Rather, you activate them to execute tasks in response to an event or action. 

In the usually distributed infrastructure, these functions act as the glue between various application components: the source for one element and the destination for the other.

This is why you should examine the permissions connected with the function and do so with the principle of least privilege.

Let’s take, for example, a function that only needs read access to your system’s database but can delete and create cloud resources under your account.

If you deploy malicious code on that function, your cyber adversary can overthrow your whole system by eliminating production resources or creating numerous dummy resources. Your attacker can then clear out your account quota. These incidents endanger your application’s availability.

Revisiting and scaling back who has which access permission level is often burdensome. However, you need to do so rigorously to ensure your platform’s security.

3. Keep sensitive data in secure storage locations.

Store your business-critical data assets and keys in secrets management solutions. Opt for these storage locations over (or other than) static files in source code repositories and environment variables. Doing so minimizes the risk of exposing sensitive information.

You can use secrets management solutions provided natively on cloud platforms. These tools allow you to store and retrieve arbitrary values safely. They also offer authentication and other functions supported by the identity access management (IAM)’s solution. Alternatively, you can build and deploy your company’s secrets management tool. 

4. Secure your communicated transit data.

Investing in network design security can help protect your business and its transit data from risks and threats. Moreover, using secure web communication channels is among your best cybersecurity defenses against online attacks. This tactic lets you closely monitor functions integrating with third-party services.

Here are ways to ensure the safe communication of your transit data:

• Take advantage of HTTPS and TLS.  

Cyber adversaries can exploit unprotected communication channels and unverified algorithms to pull out confidential data. Minimize these security breaches by using certified-secure communication channels within your functions’ or services’ internal perimeters. This action encrypts transmitted information with correct cryptographic algorithms.

• Restrict illegal access to resources. 

Execute the right access control mechanisms, e.g., verifying SSL certifications and defaulting to access denial. The former ensures that users and servers maintain secure communications. 

It also stops unauthorized data exchanges when the server’s identity and authenticity don’t match the information on the certificate. Additionally, enable signed requests and rate-limiting for cloud vendors to reduce the chances of cybersecurity attacks and unsecured communications.

• Limit Lambda access only to your VPC.

if you use AWS Lambda, launch its functions inside private subnets in a virtual private cloud (VPC) under your AWS account. Doing so lets you set up restricted communications between a private network and a Lambda function for cache instances, databases, internal services, and other resources.

5. Apply secure coding conventions.

Serverless architecture carries new cybersecurity threats which traditional tools cannot effectively mitigate. 

This led to the emergence of several secure coding frameworks you can readily apply to your business application.

Requiring secure coding from your DevOps team fortifies your application’s code, especially if it serves as your organization’s lifeblood. 

It also promotes the best cybersecurity activities, e.g., regular application audits, to arrest issues and vulnerabilities early.

Take a look at some of the top practices recommended by the Open Web Application Security Project (OWASP) that apply to serverless platforms:

• Execute every function as a nano service with specific access controls. 

Broken access control in serverless functions can widen your exposure to cybersecurity threats. Traditional tools authorize access to the entire platform and use single tokens for all functions. As a unified authentication, the token controls access to the platform. Implementing functions as nano services with individual access control sets can restrict entry to unauthorized components.

• Implement minimum user input.

 Injection attacks, where data is not filtered or encoded with the proper context, can be rendered as part of unsecured executions. These threats usually apply to executions on a database, system, CSS code, and HTML. Minimizing user input lessens cyber attackers’ chances to insert data through message queues, new or modified database fields and files, and other events usually triggered by unsecured serverless functions.

Ensure your application’s serverless security now.

Developing applications with serverless frameworks brings several business benefits. However, modern cybersecurity threats loom at scale. So, do everything to improve your application’s security posture and DevOps team collaboration at the onset. This helps you dodge any potential hacker onslaughts and protect your business’ profitability and even sustainability.