The new versions of 1password with subscription forces you to store your vaults onto their servers. That is what "centralized database" means. It means ALL the users of 1password must store their vaults onto 1 central point : Agile's servers only.
The point is that they don't allow local vaults anymore. The more data is centralised onto 1 node, the more it becomes a valuable target. It means an exponentially higher risk in case a point of failure is found.
1password 7 is already much less secure than previous versions :
"This was most evident in 1Password7 where secrets, including the master password and its associated secret key, were present in both a locked and unlocked state. This is in contrast to 1Password4, where at most, a single entry is exposed in a “running unlocked” state and the master password exists in memory in an obfuscated form, but is easily recoverable. If 1Password4 scrubbed the master password memory region upon successful unlocking, it would comply with all proposed security guarantees we outlined earlier."
There’s new research on the security of password managers, specifically 1Password, Dashlane, KeePass, and Lastpass. This work specifically looks at password leakage on the host computer. That is, does the password manager accidentally leave plaintext copies of the password lying around memory...
www.schneier.com
"The memory “hygiene” of 1Password7 is so lacking, that it is possible for it to leak passwords from memory without an intentional attack at all. During our evaluation of 1Password7, we encountered a system stop error (kernel mode exception) on our Windows 10 workstation, from an unrelated hardware issue, that created a full memory debug dump to disk. While examining this memory dump file, we came across our secrets that 1Password7 held cleartext, in memory, in a locked state when the stop error occurred"
Password managers allow the storage and retrieval of sensitive information from an encrypted database. Users rely on them to provide better security guarantees against trivial exfiltration than alternative ways of storing passwords, such as an unsecured flat text file. In this paper we propose...
www.ise.io