RefreshToken Is Exposed

• Query id: 5b48c507-0d1f-41b0-a630-76817c6b4189
• Query name: RefreshToken Is Exposed
• Platform: CloudFormation
• Severity: Medium
• Category: Secret Management
• URL: Github

Description

Alexa ASK Skill AuthenticationConfiguration RefreshToken should not be a plaintext string
Documentation

Code samples

Code samples with security vulnerabilities

Positive test num. 1 - yaml file

Resources:
  MySkill:
    Type: "Alexa::ASK::Skill"
    Properties:
      SkillPackage:
        S3Bucket: "my-skill-packages"
        S3Key: "skillpackage.zip"
        S3BucketRole: !GetAtt S3BucketReadRole.Arn
        Overrides:
          Manifest:
            apis:
              custom:
                endpoint:
                  uri: !GetAtt SkillFunction.Arn
      AuthenticationConfiguration:
        ClientId: "amzn1.application-oa2-client.1234"
        ClientSecret: "1234"
        RefreshToken: "Atzr|1234"
      VendorId: "1234"

Positive test num. 2 - json file

{
  "Resources": {
    "MySkill": {
      "Type": "Alexa::ASK::Skill",
      "Properties": {
        "VendorId": "1234",
        "SkillPackage": {
          "S3Bucket": "my-skill-packages",
          "S3Key": "skillpackage.zip",
          "S3BucketRole": "S3BucketReadRole.Arn",
          "Overrides": {
            "Manifest": {
              "apis": {
                "custom": {
                  "endpoint": {
                    "uri": "SkillFunction.Arn"
                  }
                }
              }
            }
          }
        },
        "AuthenticationConfiguration": {
          "ClientId": "amzn1.application-oa2-client.1234",
          "ClientSecret": "1234",
          "RefreshToken": "Atzr|1234"
        }
      }
    }
  }
}

Code samples without security vulnerabilities

Negative test num. 1 - yaml file

Resources:
  MySkill:
    Type: "Alexa::ASK::Skill"
    Properties:
      SkillPackage:
        S3Bucket: "my-skill-packages"
        S3Key: "skillpackage.zip"
        S3BucketRole: !GetAtt S3BucketReadRole.Arn
        Overrides:
          Manifest:
            apis:
              custom:
                endpoint:
                  uri: !GetAtt SkillFunction.Arn
      AuthenticationConfiguration:
        ClientId: "amzn1.application-oa2-client.1234"
        ClientSecret: "1234"
        RefreshToken: "{{resolve:secretsmanager:Atzr|IQEBLzAtAhRPpMJxdwVz2Nn6f2y-tpJX2DeX}}"
      VendorId: "1234"
  MySkill2:
    Type: "Alexa::ASK::Skill"
    Properties:
      SkillPackage:
        S3Bucket: "my-skill-packages"
        S3Key: "skillpackage.zip"
        S3BucketRole: !GetAtt S3BucketReadRole.Arn
        Overrides:
          Manifest:
            apis:
              custom:
                endpoint:
                  uri: !GetAtt SkillFunction.Arn
      AuthenticationConfiguration:
        ClientId: "amzn1.application-oa2-client.1234"
        ClientSecret: "1234"
        RefreshToken: "{{resolve:ssm-secure:Atzr|IQEBLzAtAhRPpMJxdwVz2Nn6f2y-tpJX2DeX}}"
      VendorId: "1234"

Negative test num. 2 - json file

{
  "Resources": {
    "MySkill": {
      "Type": "Alexa::ASK::Skill",
      "Properties": {
        "SkillPackage": {
          "S3Bucket": "my-skill-packages",
          "S3Key": "skillpackage.zip",
          "S3BucketRole": "S3BucketReadRole.Arn",
          "Overrides": {
            "Manifest": {
              "apis": {
                "custom": {
                  "endpoint": {
                    "uri": "SkillFunction.Arn"
                  }
                }
              }
            }
          }
        },
        "AuthenticationConfiguration": {
          "ClientId": "amzn1.application-oa2-client.1234",
          "ClientSecret": "1234",
          "RefreshToken": "{{resolve:secretsmanager:Atzr|IQEBLzAtAhRPpMJxdwVz2Nn6f2y-tpJX2DeX}}"
        },
        "VendorId": "1234"
      }
    },
    "MySkill2": {
      "Type": "Alexa::ASK::Skill",
      "Properties": {
        "SkillPackage": {
          "S3Bucket": "my-skill-packages",
          "S3Key": "skillpackage.zip",
          "S3BucketRole": "S3BucketReadRole.Arn",
          "Overrides": {
            "Manifest": {
              "apis": {
                "custom": {
                  "endpoint": {
                    "uri": "SkillFunction.Arn"
                  }
                }
              }
            }
          }
        },
        "AuthenticationConfiguration": {
          "ClientId": "amzn1.application-oa2-client.1234",
          "ClientSecret": "1234",
          "RefreshToken": "{{resolve:ssm-secure:Atzr|IQEBLzAtAhRPpMJxdwVz2Nn6f2y-tpJX2DeX}}"
        },
        "VendorId": "1234"
      }
    }
  }
}