Hi,
Yes, you can change it if you have access to the PlatformAdmin of your unity connections server. Unity connections uses the Security Password to access the Database between the publisher and subscribers. To change your security password you need to log into the CLI mode of the Connections and do the following..
CLI>set password security
on the publisher and follow the instructions to change the password. Also make sure that you set the same password to all the other subscribers in order to have agood replication of the database. You can cross verify the below link from cisco.
http://www.cisco.com/en/US/partner/docs/voice_ip_comm/connection/7x/installation/guide/7xcucig020.html#wp187758
Please rate if that helps!
Mohsin..
