Despite all the benefits serverless platforms bring to application developers, the security of serverless applications is still a concern. This is because serverless infrastructure is managed by third-party service providers; developers have limited access to the security settings for serverless environments.
In this article, we list major security challenges and risks of serverless applications and explore best practices for improving the security of your serverless solution. This article will be helpful for developers who are considering using serverless technology for their projects and want to do so securely.
Serverless applications and responsibilities
Serverless applications are cloud-based software built using serverless computing — a type of architecture where an application runs in event-triggered stateless compute containers that are fully managed by service providers.
Security risks and vulnerabilities
Building solutions using rented servers means storing sensitive user data somewhere you don’t completely control. Thinking of serverless security is crucial, as data leaks can cause scandals and damage reputations.
There have been some well-known security breaches caused by attacks on cloud servers:
- In 2016, over 93 million voter registration records were compromised in Mexico. The reason was a poorly configured database illegally hosted on an Amazon cloud server outside of Mexico.
- The Timehop application suffered from an attack in 2018 in which the names and emails of 21 million users were compromised. The attacker abused Timehop admin credentials to access the application’s cloud environment.
Records of more than 100 million Capital One customers were compromised in 2019. A cloud misconfiguration allowed a malicious actor to access credit card applications, social security numbers, and bank account numbers of the company’s customers.
Security challenges with serverless applications
Serverless computing is still quite a new technology, so handling it is more complicated than handling traditional software environments. Software developers and architects often lack the experience needed to ensure decent serverless app security.
Choosing the right security strategy
Application security gets trickier when it comes to cloud and serverless deployments. Thus, coming up with a relevant security strategy also becomes more challenging.
The first issue is that the development team has to rely on the service vendor to ensure the security of the solution. Before starting to collaborate with a service provider, you need to ensure they can maintain your application’s security at an appropriate level and protect your data and intellectual property from theft.
Lack of comprehensive security testing
Security officers and testers often face additional challenges when testing the security of serverless solutions. Even more challenges arise when serverless applications interact with cloud storage, remote third-party services, databases, and backend cloud services.
Outdated and vulnerable third-party libraries
When you use a serverless platform, you’re most likely relying on third-party libraries — which often depend on additional libraries themselves — for your application to function. This is a conventional and helpful way to speed up development. However, libraries may also attract hackers who use their known and yet unknown vulnerabilities to start an attack.
Best practices to enhance security in serverless applications
Since serverless architecture is a relatively new approach, it’s susceptible to the security issues we’ve mentioned. While serverless providers are working on eliminating these risks, you should follow best practices to eliminate those security risks that are your responsibility.
Devise a comprehensive security strategy
Consider all the risks and challenges your serverless application can face and create a robust security strategy to avoid major pitfalls right from the start.
Here are a few useful tips for improving your security strategy:
- Validate event and input data that comes from HTTP/HTTPS traffic to the serverless application.
- Explore your security policies and access permissions in detail.
- Consider implementing the principle of least privilege and giving each function minimum permissions.
- Perform static code analysis and conduct penetration testing to detect vulnerabilities.
Combine the best of existing testing practices
Serverless applications can be more challenging to test than traditional ones. Even basic methods and techniques like stress testing and fuzzing can make a big difference in serverless application security testing. Therefore, security engineers have to analyze the function code itself to identify flaws in business logic and improper use of APIs and data types.
Creating an application using a serverless architecture is a great way to reduce development costs and ensure the scalability of your solution. However, your development team has to keep potential security issues in mind right from the start.
Making sure that your serverless application is secure isn’t easy. Insecure deployment configurations, insufficient monitoring, and a lack of comprehensive security testing increase the risk of a security incident. However, these issues can be addressed by combining different types of testing techniques, following security coding guides, and securing event input to avoid malware injection.