The goal of this document is to detail the rationales behind why various technologies and processes are encouraged or discouraged. All Mozilla sites and deployment should follow the recommendations below. The Security Assurance and Security Operations teams maintain this document as a reference guide.
|Shared passwords are passwords or/and accounts that more than one person knows or has access to. They're discouraged because:
§ Password reuse
|Password reuse is the practice of a single user using the same password across multiple different accounts/sites. This is contrasted with creating a different, distinct password for every account/site. Users often employ hybrid forms of password reuse like
Password reuse is discouraged because:
Note that it is dangerous for a user to rely on a site being able to effectively prevent an attacker from obtaining that user's password once an attacker has compromised the site.
Since it's difficult/impossible for a user to memorize a distinct password for every account/site, a common solution is to use a password manager.
§ Decentralized user account management
|Decentralized user account management refers to user account management which is not driven by the source of truth for the user's account. Examples of this are:
This practice is discouraged because:
§ Multi-factor Authentication
|Multi-factor authentication (MFA) is a security system that requires more than one method of authentication from independent categories of credentials to verify the user's identity for a login or other transaction.
Requiring the use of MFA for internet accessible endpoints is encouraged because by requiring not only something the user knows (a knowledge factor like a memorized password) but also something that the user has (a possession factor like a smartcard, yubikey or mobile phone) the field of threat actors that could compromise the account is reduced to actors with physical access to the user.
In cases where the possession factor is digital (a secret stored in your mobile phone) instead of physical (a smartcard or yubikey), the effect of MFA is not to reduce the field of threat actors to only those that have physical access to the user, because a secret can be remotely copied off of a compromised mobile phone. Instead, in this case, the possession factor merely makes it more difficult for the threat actor since they now need to brute force/guess your password and compromise your mobile phone. This is, however, still possible to do entirely from a remote location. In particular, storing both first and second factor on the same device (for example: mobile phone) is strongly discouraged.
§ Network Security Monitoring
|Network Security Monitoring (NSM) is the practice of monitoring raw network traffic in order to detect intrusions or abnormal behavior. The use of NSM is encouraged because it can: