Privacy-Preserving Password Breach Check

Omega Security Pro'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 Pwned Passwords 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