PaaS Clouds offer a comprehensive environment that provides developers with the tools to build, test, and deploy applications efficiently in the cloud.PaaS Clouds streamline the development process by offering infrastructure management, middleware, and core services alongside application development tools. This integrated approach enables developers to focus on application functionality rather than infrastructure concerns, which accelerates the software development lifecycle and potentially...
You have many attack vectors.
Firstly, there are the attack vectors that are part of your application and environment but these will be the same independent of where you are.
Beyond that you have the following ones:
1) Anybody with access to the PaaS infrastructure either internal or external.
2) Accidental mistagging of data (think of accidentally setting an S3 bucket as public).
3) The provider monetizing your data (take a look at the troubles currently surrounding Oracle)
4) large cloud providers are subject to constant attacks because they are well-known addresses.
Private systems are still subject to attacks but not on the same level of intensity or as often by serious hackers.
The best solution for PaaS protection is always native tools... from the CSP.