A company’s application uses standard tier SecureString parameters from AWS Systems Manager Parameter Store.

Comprehensive and Detailed 100to 150 words of Explanation From AWS Certified Security – Specialty topics:

Parameter Store uses AWS KMS to encrypt SecureString parameter values when they are created or changed. When a customer managed key is used, the caller needs explicit KMS permissions, including kms:Encrypt for creating or updating SecureString values. If the application lacks that permission, the update fails. A disabled KMS key also causes failures because AWS KMS cannot perform cryptographic operations with a disabled key. A customer managed key can encrypt many SecureString parameters; existing use by another parameter is not a problem. Standard tier SecureString parameters can use customer managed keys. Using an alias instead of a key ID is also supported, so the alias is not the cause.

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