Allow incremental hashes for those of us who are not permitted to use the API
Different organizations have different security postures. Your list of hashes may be transferred into secure systems in text format where they are processed in order to match against internal password databases.
Unfortunately, despite the k-anonymity interface, exfiltrating even a partial password hash is forbidden. Given this use case, I believe it would be advantageous to provide incremental hash lists for every addition made to the database between major releases of the complete list. Daily, or even weekly would be good.
The objective would be to notify users immediately if the hash of their current password is ever added to the list rather than having an exposure gap (in this case from November 19th 2020 (V7) until v8 is released).
Michael
shared this idea
Deltas are infeasible because it’s not just new hashes being added, it’s the counts on existing ones changing too. Best bet is to either load the complete hash set or use the public API. I understand different security postures with regards to using the API, but this is why it implements k-anonymity which there shouldn’t be a practical barrier against using, at least not from a privacy perspective.