Hi @GNSGnanasekar,
Do you mean that you could see the attachments in this shared app (which built on CDS entity), but the end users could not?
Do the end users have enough permission to access your CDS Entity?
I have made a test on my side, and don't have the issue that you mentioned. Please check the attached GIF screenshot for more details.
If you create an app based on CDS for Apps, you must also ensure that the users with whom you share the app have the appropriate permissions for the entity or entities on which the app relies.
Please check if you have assigned a proper security role (which have appropriate permissions to access your CDS Entity) to your users in your PowerApps environment.
More details about managing CDS Entity permission in PowerApps, please check the following article:
https://docs.microsoft.com/en-us/powerapps/maker/canvas-apps/share-app#manage-entity-permissions
More details about sharing a canvas app built on CDS Entity, please check the following blog:
https://powerapps.microsoft.com/en-us/blog/sharing-a-canvas-app-built-on-top-of-common-data-service/
Please also take a try to re-create a new app based on your CDS Entity, then share it with your users, check if the issue is solved.
Best regards,
Kris