Platform as a service

In a PaaS-based offering, the provider will allow consumers to host their own application onto their cloud infrastructure.

The PaaS provider, in turn, handles the backend support of the programming languages, libraries, and associated tools that allow a consumer to upload and manage their application. The consumer does not have to worry about underlying servers, OS, networks, and platform security as they're handled by the PaaS provider.

However, the hosted application's security and configuration is still the responsibility of the customer.

Google App Engine, which is part of the Google Cloud Platform, is one famous example. All we have to do is to upload our code and all backend stuff will be managed by them. However, if the code itself is vulnerable, then it is the responsibility of the customer and not the PaaS provider: