AWS Lambda

According to AWS, Lambda is "a serverless, event-driven compute service that lets you run code for virtually any type of application or backend service without provisioning or managing servers."

While that's a mouthful of marketing jargon, what does that mean?

"Serverless" is the concept that you, as the end-user, do not need to build or deploy any infrastructure to run a Lambda function. AWS manages all that for you. AWS claims you can "Simply write and upload code as a .zip file." In reality, each Lambda is a function that runs in its own container with multiple isolation layers between AWS customers. But all of that is abstracted away from the customer by AWS.

Lambda supports a number of languages (opens in new tab), called runtime environments. The most popular are NodeJS, Python, Java, and Go. 

"Event-driven (opens in new tab)" is what happens after you upload your code. All Lambda functions are triggered by an event. That event can be a manual invocation of the function or tied to other activities in the account, such as a console login or a user writing an object to an S3 bucket. This event-driven nature allows you to create complex applications based on multiple AWS services. 

Because Lambda functions are event-driven, they have a few limitations. The most significant limitation is that a Lambda function can run for no longer than 15 minutes before it times out. 

AWS Lambda is one of the next frontiers of cloud-native applications, so it's important to know how they work, how to create them securely, and how they can be attacked. Additionally, many cloud security tools leverage Lambda to manage security events, so as a cloud security practitioner, you will need to be able to build with Lambda.

Learning Objectives

• Understand the benefits and limitations of AWS Lambda service and Lambda functions
• Learn about the various components and settings for a Lambda function
• Understand the multiple ways a developer or operator can misconfigure a Lambda function to make it less secure.