Security issue on Synology with Minimserver

[woldejans]

I run Minimserver on my Synology (DS215+, latest software). Runs fine.
Some other people can use my Synology too for p.e. PhotoStation. They have only rights to use their personal photo map with there own login. All other maps (including Minimserver) are forbidden.
This morning I saw something strange when login in as of these users. Everyone has access to the Minimserver application!
I checked, double checked the security and access-settings but I can find no reason why other users have rights to see but also make changes to Minimserver.
Not sure if this is a Minimserver of a Synology issue, but if anyone has a solution.........?

Willem.