[Mikescher]

I'm no cryptographic expert, but I always liked the simple design of the kdbx files. So simple that I can understand it and see tat there are no (obvious, assuming the underlying algorithms are called correctly) problems:

The whole database is a single big xml document which is then encrypted with a normal symmetrical encryption method (most of the time AES). And that is already the core of it. There are a few additional things (A user-chosen key-derivation-function is used to increase the brute-force time and there is a header in the binary format with such things as keepass version, which algorithms are used for encrypting and a checksum...).

But in comparison to other cloud-based password managers it's a nice feeling to intuitively "know" whats happening under the hood.