Required prior knowledge
The Saphe solution documentation assumes that the reader has some understanding of how the Internet and the World-Wide-Web work (for example: IP addresses and routing, HTTP, etc.) and a basic understanding of cryptographic concepts (AES, SHA-1, HMAC, SSL, etc.).
The purpose of Saphe is to prevent the user's password from ever being sent unencrypted or to the wrong server. It does not matter if the user was somehow solicited to connect to a malicious server; unless the server can authenticate itself to the to user - his personal information is saphe!
It is assumed that any web-site or web-based service that is valuable enough to be Phished requires a password to identify its users, and that the objective of any Phishing attack is first and foremost to obtain this password.
Therefore, the Saphe solution relies on the fact that both the user and the real server have knowledge of this password and that any would-be attacker does not (or else there is no point to conduct a Phishing attack in the first place) in order to authenticate the server to the user. After the server was successfully – and automatically – authenticated as the real server, a secure (SSL) connection is established between the client and the server, through which the password can be sent to the server in order to authenticate the user to the server. After that the login process continues normally.
However, proving that the server at the other end of the line is in fact the real server is not enough - we also need to ensure that there is no Man-in-the-Middle of any type. To solve this problem, the Saphe solution uses the user password to encrypt data that can prove to the user that the connection itself is tamper-free, and that no malicious entities can see or alter the data.
Note that any denial-of-service attack is acceptable, as long as the user's private information has not been compromised. This solution does not include any protection from DoS attacks.
See an overview of the solution in this presentation:
General implementation notes
The Saphe solution is based on the cooperation between server-side code and client-side code (browser plugin), which communicate over a secure (SSL) connection to authenticate the user and the server to each other.
On the user's part - the plugin should present visible effects that cannot be duplicated by any web-based code.
See Solution details for much more information!
Find out more
- Solution security assumptions
- Solution details
- Thwarting Phishing scenarios
- Implementation documentation
- Ease of use
- Potential problems
- Future features