Serverless API Without Content Encoding

• Query id: a2f2800e-614b-4bc8-89e6-fec8afd24800
• Query name: Serverless API Without Content Encoding
• Platform: CloudFormation
• Severity: Medium
• Category: Encryption
• URL: Github

Description

AWS Serverless API should enable Content Encoding through the attribute 'MinimumCompressionSize'. This value should be greater than -1 and smaller than 10485760
Documentation

Code samples

Code samples with security vulnerabilities

Positive test num. 1 - yaml file

AWSTemplateFormatVersion: '2010-09-09'
Transform: AWS::Serverless-2016-10-31
Description: AWS SAM template with a simple API definition
Resources:
  ApiGatewayApi:
    Type: AWS::Serverless::Api
    Properties:
      StageName: prod
      TracingEnabled: true
      CacheClusterEnabled: true
      AccessLogSetting:
        DestinationArn: 'arn:aws:logs:us-east-1:123456789:log-group:my-log-group'
        Format: >-
          {"requestId":"$context.requestId", "ip": "$context.identity.sourceIp",
          "caller":"$context.identity.caller",
          "user":"$context.identity.user","requestTime":"$context.requestTime",
          "eventType":"$context.eventType","routeKey":"$context.routeKey",
          "status":"$context.status","connectionId":"$context.connectionId"}

Positive test num. 2 - yaml file

AWSTemplateFormatVersion: '2010-09-09'
Transform: AWS::Serverless-2016-10-31
Description: AWS SAM template with a simple API definition
Resources:
  ApiGatewayApi2:
    Type: AWS::Serverless::Api
    Properties:
      StageName: prod
      TracingEnabled: true
      CacheClusterEnabled: true
      AccessLogSetting:
        DestinationArn: 'arn:aws:logs:us-east-1:123456789:log-group:my-log-group'
        Format: >-
          {"requestId":"$context.requestId", "ip": "$context.identity.sourceIp",
          "caller":"$context.identity.caller",
          "user":"$context.identity.user","requestTime":"$context.requestTime",
          "eventType":"$context.eventType","routeKey":"$context.routeKey",
          "status":"$context.status","connectionId":"$context.connectionId"}
      MinimumCompressionSize: -1

Positive test num. 3 - yaml file

AWSTemplateFormatVersion: '2010-09-09'
Transform: AWS::Serverless-2016-10-31
Description: AWS SAM template with a simple API definition
Resources:
  ApiGatewayApi3:
    Type: AWS::Serverless::Api
    Properties:
      StageName: prod
      TracingEnabled: true
      CacheClusterEnabled: true
      AccessLogSetting:
        DestinationArn: 'arn:aws:logs:us-east-1:123456789:log-group:my-log-group'
        Format: >-
          {"requestId":"$context.requestId", "ip": "$context.identity.sourceIp",
          "caller":"$context.identity.caller",
          "user":"$context.identity.user","requestTime":"$context.requestTime",
          "eventType":"$context.eventType","routeKey":"$context.routeKey",
          "status":"$context.status","connectionId":"$context.connectionId"}
      MinimumCompressionSize: 11485759

Code samples without security vulnerabilities

Negative test num. 1 - yaml file

AWSTemplateFormatVersion: '2010-09-09'
Transform: AWS::Serverless-2016-10-31
Description: AWS SAM template with a simple API definition
Resources:
  ApiGatewayApi4:
    Type: AWS::Serverless::Api
    Properties:
      StageName: prod
      TracingEnabled: true
      CacheClusterEnabled: true
      AccessLogSetting:
        DestinationArn: 'arn:aws:logs:us-east-1:123456789:log-group:my-log-group'
        Format: >-
          {"requestId":"$context.requestId", "ip": "$context.identity.sourceIp",
          "caller":"$context.identity.caller",
          "user":"$context.identity.user","requestTime":"$context.requestTime",
          "eventType":"$context.eventType","routeKey":"$context.routeKey",
          "status":"$context.status","connectionId":"$context.connectionId"}
      MinimumCompressionSize: 114