[Owncloud] Foreigners on the same Instance?

[Henning Schuster]

Hi ownCloud Users and Devs,

I'm using ownCloud 4.5 for some weeks now and I'm pretty impressed. Nice piece of software!

The company I'm working for thinks about offering ownCloud to their customers in the future. We want to setup different instances for teams. However, single users which are not connected to each other (they don't work for the same company and they don't know each other) should share the same instance. Single users must not see each other and must not share files.

Would you say it is save to put foreigners on the same instance? Is there a high risk that a user that is logged in with a valid account is able to use vulnerabilities of ownCloud to access, modify or delete data of other users on the same instance?

Best,
Henning