Insecure interfaces and APIs can expose data to unauthorized users, which is a significant security risk. If the API or interface is not properly secured with authentication, authorization, and encryption measures, attackers may exploit vulnerabilities to gain unauthorized access to sensitive data or control over cloud services. This can lead to data breaches and loss of confidentiality.

Ensuring secure data encryption at rest is important, but it is not directly related to insecure interfaces and APIs, which are more about securing data during transmission or interaction. Man-in-the-middle attacks can occur if APIs and interfaces are not properly secured with encryption, but this is a more specific type of attack rather than the primary risk. Increased resource consumption on servers is not typically associated with insecure interfaces or APIs. This might be a result of other issues, like poorly optimized APIs.