Privacy-Preserving Password Breach Check

AutoSecurityApp's optional breach check uses a k-anonymity workflow. The password is hashed locally with SHA-1, and only the first five hexadecimal characters of that hash are sent to the breach-range service. The response contains candidate suffixes, which are compared locally.

This reduces disclosure compared with sending a password or full password hash, but it is still an online request and is only performed when the user chooses the breach-check action.

Open Password Tools