Why is 1Password over Dropbox the "worst of both worlds"? Seems like it's potentially safer, because it's encrypted with your passphrase and also your dropbox credentials. Sure, the NSA can probably get it, but J Random Hacker can't.
Whether or not they can break the Keepass encryption after getting your data is debatable but strikes me as "probably yes."
https://nakedsecurity.sophos.com/2011/06/21/dropbox-lets-any...
From my admittedly small knowledge of encryption I would assume that such a set of data could be used to greatly decrease the size of the search-space for the decryption key.
There are a few people experts who post here, anyone care to comment?
Formally, if your cipher would weaken in a way that makes practical attacks possible as more data is encrypted, it would be considered broken. Furthermore, it is possible to work around this by rotating keys and just encrypting the keys in a master file. 1Password definitely uses encryption keys that are fully independent from your master password, although I don't know if they periodically use new keys for new data.
- Dropbox uses Secure Sockets Layer (SSL)/Transport Layer Security (TLS) to protect data in transit between Dropbox apps and our servers; it's designed to create a secure tunnel protected by 128-bit or higher Advanced Encryption Standard (AES) encryption.
Source: https://www.dropbox.com/help/27