The data is probably is somewhat safe in the cloud. I expect what’s infected is a bunch of PC clients locally. The logical thing that could have happened is someone with an admin level of access on the Windows domain opened an attachment or got phished, and that allowed the ransomware to deploy to all the on-prem systems. Unless they have customized the ransomware to do anything special for this particular library software, it may be not all that bad in terms of data at risk. Though it’s possible the human attackers received cloud software credentials, and could have used that to exported patron data to threaten to leak.