4 ms·

Is it safe to assume that 1Password has some sort of data feed from HIBP to handle this locally? I can't imagine they are calling a service out of their control

Is it safe to assume that 1Password has some sort of data feed from HIBP to handle this locally? I can't imagine they are calling a service out of their control to send your passwords or email addresses (or even hashes of them), no? That was the only concern part for me and unless I missed it I couldn't find where it was addressed. Beyond that this is a great idea!

londons_explore 9y ago
Anyone can download the whole list of hashes
eridius 9y ago
HIBP now has an API for testing if passwords have been pwned that preserves the secrecy of the password. It's called k-anonymity, and you can read about it in the second half of https://www.troyhunt.com/ive-just-launched-pwned-passwords-version-2/ https://www.troyhunt.com/ive-just-launched-pwned-passwords-v...
- ninkendo 9y ago
  I figure it’s easy to do something like this by generating a nonce over a TLS connection and using it as a shared salt value, and just checking if the hashes of the two passwords match when using the nonce as a salt. Not sure what k-anonymity is but I wouldn’t be surprised if it’s something similar. Edit: nope, looks like k-anonymity basically lets you search by the first few characters of the sha512 hash, and it responds with all of the hashes that have that as the first few characters, along with the count for each (how many people use that password, likely.)
  - eridius 9y ago
    Yeah. It produces a response that’s small, easy and fast to generate, easy and fast to parse, without actually telling the server much of anything (all the server learns is that it isn’t a password whose hash starts with something else, but that barely narrows the search space).
  - tonyztan 9y ago
    Direct link to k-anonymity section: https://www.troyhunt.com/ive-just-launched-pwned-passwords-version-2/#cloudflareprivacyandkanonymity https://www.troyhunt.com/ive-just-launched-pwned-passwords-v...
- Sylos 9y ago
  Mozilla also uses this k-anonymity in their implementation of Google Safe Browsing. (As they need to ask Google's server, if the webpage you're visiting or the file you're downloading is safe, without telling Google the webpage/file that you are visiting/downloading.) Pretty good documentation on that: https://feeding.cloud.geek.nz/posts/how-safe-browsing-works-in-firefox/ https://feeding.cloud.geek.nz/posts/how-safe-browsing-works-... Another idea here, stolen from Mozilla's implementation, would be to add in a few noise entries when making a request. So, if the user types in their password and the hash evaluates to "2e78f...", you would send off the request for that range and also send off requests for a handful of random, other ranges. In effect, this isn't particularly different from using less symbols to denote the range, e.g. asking for "2e78" instead of "2e78f". But that gives you 16 times as many results, whereas with noise entries, you can fine-tune it to give you for example only 5 times as many results (with 4 noise entries, that is).
bdcravens 9y ago
They already have the Watchtower service in 1Password that audits your passwords: "Your website information is never transmitted to the 1Password Watchtower service"

londons_explore 9y ago

Anyone can download the whole list of hashes

eridius 9y ago

HIBP now has an API for testing if passwords have been pwned that preserves the secrecy of the password. It's called k-anonymity, and you can read about it in the second half of https://www.troyhunt.com/ive-just-launched-pwned-passwords-version-2/ https://www.troyhunt.com/ive-just-launched-pwned-passwords-v...

ninkendo 9y ago
I figure it’s easy to do something like this by generating a nonce over a TLS connection and using it as a shared salt value, and just checking if the hashes of the two passwords match when using the nonce as a salt. Not sure what k-anonymity is but I wouldn’t be surprised if it’s something similar. Edit: nope, looks like k-anonymity basically lets you search by the first few characters of the sha512 hash, and it responds with all of the hashes that have that as the first few characters, along with the count for each (how many people use that password, likely.)
- eridius 9y ago
  Yeah. It produces a response that’s small, easy and fast to generate, easy and fast to parse, without actually telling the server much of anything (all the server learns is that it isn’t a password whose hash starts with something else, but that barely narrows the search space).
- tonyztan 9y ago
  Direct link to k-anonymity section: https://www.troyhunt.com/ive-just-launched-pwned-passwords-version-2/#cloudflareprivacyandkanonymity https://www.troyhunt.com/ive-just-launched-pwned-passwords-v...
Sylos 9y ago
Mozilla also uses this k-anonymity in their implementation of Google Safe Browsing. (As they need to ask Google's server, if the webpage you're visiting or the file you're downloading is safe, without telling Google the webpage/file that you are visiting/downloading.) Pretty good documentation on that: https://feeding.cloud.geek.nz/posts/how-safe-browsing-works-in-firefox/ https://feeding.cloud.geek.nz/posts/how-safe-browsing-works-... Another idea here, stolen from Mozilla's implementation, would be to add in a few noise entries when making a request. So, if the user types in their password and the hash evaluates to "2e78f...", you would send off the request for that range and also send off requests for a handful of random, other ranges. In effect, this isn't particularly different from using less symbols to denote the range, e.g. asking for "2e78" instead of "2e78f". But that gives you 16 times as many results, whereas with noise entries, you can fine-tune it to give you for example only 5 times as many results (with 4 noise entries, that is).

bdcravens 9y ago

They already have the Watchtower service in 1Password that audits your passwords: "Your website information is never transmitted to the 1Password Watchtower service"