Table of Contents
This is a work-in-progress, please check back later for the final draft
Overview
With the rise of technology, the world around us has been constantly changing. However, one thing has remained predominantly the same throughout all these years: how we prove we are who we say we are over the wire. If you have ever created an account to utilize an online service, you had to provide a username and/or email along with a password. Maybe that service already had the username you wanted, the password you choose did not meet the seemingly arbitrary rules they put forth, or already had your email or username registered and you've now realized you've forgotten your password. If you have never not enjoyed any part of this process, you are not alone and this manifesto was written for you and others who feel the same way and want something better.
The State Of User Authentication
For every online service that allows for individuals to create accounts to become users in their system, there must be a system in place to differentiate one user from another (identification) and to prevent users from logging on as others (authentication). This is typically handled by using a username for identification and a password for authentication. In most cases, usernames and passwords are decided by the user and they must abide by the parameters decided by the service (typically to prevent duplicate usernames and simple passwords). Many websites will also include an email address as either additional account information or to act in place as the username. This is typically done to mitigate flooding of bot accounts, a means to communicate with the user during password resets, and/or a method to communicate additional information to the user over time.
To allow for authentication to take place, the identification credentials (username) upon logging in must be supplied with the authentication credentials (password) to verify if they match with the pair stored with the online service. In the event that the user cannot login due to forgetting/losing their authentication credentials, the user's account can be recovered either through following a prompt through the user's email after submitting a request for a reset or by answering security questions. Security questions are supposed to be questions answered previously where the answers should only be known by the user to prevent identity theft. Once the user is authenticated, a cookie or token is typically assigned to the user so that they can continue to navigate through the user-only pages of the service during their session without having to consistently authenticate themselves.
The Problem
Online services fill a number of roles ranging from entertainment, where we network and socialize, a place to purchase goods and/or services, and a resource to manage our assets. In short, it is sufficiently important that these services be secure and prohibit anyone aside from the owner of the account to gain access to the account. However, the current status quo of how online accounts are setup contain many systemic points of failure.
Passwords
The intent behind a password is to allow the owner of the account to gain access while preventing everyone from getting in. This places the password as the front line of defense against anyone who would try to break into an account, so it should be the strongest part of this system to prevent would-be attacker. However, the strength and integrity of passwords are created by users that do not know the proper security measures that should be taken for creating and managing passwords. This leads to situations where many users will choose the same easy to guess password1 or using passwords that are easy to crack through brute-forcing by current systems (this includes 8 character, mixed-case, alphanumeric + symbols passwords).
The trouble here is that given the complexity needed to create sufficient passwords, it leaves for passwords that are not easy to remember. Which leads to the second big problem with passwords, re-using passwords across multiple passwords. While nobody wants to try to remember complicated passwords, they also don't want to remember multiple different passwords. Out of laziness, necessity to remember that one good password, or having been locked out of an account prior due to not remembering which password went to it; a large group of users have decided to use the same password on different services. This greatly expands the threat vector of having one compromised account leading to others accounts sharing the same credentials becoming compromised as well.
Following the issue with password where users will share the same password across different services, using the same email creates a similar issue. The purpose email is supposed to serve is a means to electronically send messages to another individual in a fashion similar to snail mail. However, online services have created a second purpose for email, being a means to verify who a user is without the need for a password. For this reason, if a password needs to be reset, the de-facto way of resetting it is by sending a reset link to that user's email so that only they can change the password on their service.
The inherit problem here is that email uses the same username/password scheme for authenticating their users. So if a user uses an easy to crack or guessable password, the attacker can now access all of their online services that share the same email. Like how many individuals only have one mailing address, most users only have one email for the same reason. Because of the nature of how email works, if an attacker did breach a user's email they wouldn't even need to put much effort into discovering which online services the user is signed up for because they probably got an email from the service upon signing up that is still in their inbox where it can be queried by the attacker.
While the first problem with email is that it creates a single point of failure across all of the user's online services, there are other downfalls with email in the current system of user authentication. If the user makes the password for their email the same password they use on all their other services, an entirely new problem opens up. Now, not only does that one email allow an attacker to compromise all of user's services, but now if any service becomes compromised it would directly allow the user's email to become compromised as well. In this situation, which is by no means an uncommon situation for the average user, every online service is a single point of failure that can cause a rippling effect that leads to all their other services becoming compromised as well.
Service Providers
While users cannot be relied on to know the proper security measures to take, surely the developers and engineers running the online services we use would be able help mitigate against user's accounts becoming compromised? Unfortunately, the barrier of entry to create a login system for an online service does not include being taught the proper techniques for handling and storing a user's login credentials. Every year you can see multiple reports of various services (even the big names that you'd expect to know better) will have their system breached and discover that the passwords were stored as plain text2, leaving user's accounts credentials immediately compromised. The alternative is that the passwords would be hashed3 so attackers would not instantly have their hands on the user's password. However, if the passwords are simply hashed without any other precautionary steps taken, an attacker can still use a rainbow table4 to derive the passwords from their hashes without the need for brute-forcing the password.
If the above didn't all make sense, that's okay. The main take away here is that users should not trust the service providers to adequately handle their account information in the event of any security breach on their end.
User Adoption
The previous three problems are but a few in a long list of systemic issues with the current model of user authentication. While the initial thought may be "just create a new system", it's not that easy. Part of the reason all services use the same email/username/password model is because that's what users are used to and expect when they go to sign up for an online service. There have been attempts at solving the above problems by creating password managers567 to create and remember your passwords; using two-factor authentication, aka 2FA, through software8 or hardware9; and using other sites to handle user authentication10. However, these solutions are either not the defaults, require too much extra effort for the users, and/or are completely unknown to the user. For something to come in to solve the issue of user authentication at a meaningful scale it would have to solve the problems above (and more), require as more or left effort to the user, be intuitive / easy to grasp for the user (ranging from children to elders), and be adoptable by service providers to act as the new default or alternative for the current model.
Zccount
After thinking over these issues with user authentication and among many others that I've come to realize later on, I wondered if there was a way to fix this. However, before I go into explaining what Zccount is, I feel it is important to discuss what it isn't and doesn't try to solve before moving forward.
What It Is Not
User authentication is utilized in many different mediums, but I feel it's important to make a clear distinction about what use cases Zccount is not meant to apply to. To put simply, all instances of user authentication for accessing hardware. While the username / password scheme does prevent most users from accessing your device, it is much like the front door of one's house: keeps the hoi polloi from passing over the threshold of your place of inhabitance, but if anyone were to truly desire getting in there's little in the way to stop them. The simplest manner is if the drive is not encrypted, it can be mounted and read from another machine without needing to ever load the OS. There are other means to prevent against this (as mentioned, encryption is a good place to start), but this is both beyond the scope of this paper and outside the field of user authentication that Zccount tries to solve.
As well, Zccount does not and will not make any attempt to strengthen the security of one's service. While it tries to minimize the impact of one's service being breached, it alone will not prohibit nor assist in the prevention of the breach of services; Zccount strictly tries to further the default security granted to the users.
Core Principles
Keeping in mind what Zccount is not, I'll go over what Zccount is (or will try to be) by first going over it's philosophies and rules it most adhere to.
Trustless
One of the core beliefs of Zccount, and also what I believe to be the greatest issue with user authentication is the fact that one's password is sent "over the wire" to the server to be used for authentication. This both allows for man-in-the-middle11 (MITM) attacks to occur upon each authentication as well as requiring trust in the the service storing your password to keep your password safe (whether this be intentionally handing it off to a third-party or having them compromised through a security breath). For this reason, it is essential that passwords never leave the client.
The key to allowing authentication without exposing one's password is through zero-knowledge proofs12 (ZKP), a method that allows one to prove to another party that they have a password without exposing it to the other party through the means of statistics, probability, and other mathematical processes (for an example of such implementations, there's password-authenticated key agreement14). The manner ZKP's will be utilized in Zccount will be explained later on.
Diversity
As I mentioned above, one failure in the username / password scheme is that if one service is compromised, your password can then be used for accounts sharing the same password. To prevent these type of attacks, Zccount assigns a different set of credentials for each service so that if any one service is compromised it will not risk the integrity of the other services, keeping it isolated from the others. This includes both the identifier for the user as well as the verifier for the user This also provides an added layer of security in that through the credentials alone, services cannot track a user between services (where this is not the case with email).
Consent
Another way the current methods of user authentication falls short for it's users is that by default anyone can use someone's credentials from any device (including one that does not belong to the user). While at face value this may not look to be an issue, but rather a feature since it allows anyone to access their services from any device, but this should require some action by the user first beforehand. I will grant that some services get this right by either informing users when their account has been used a new machine, or even better does not allow users to access the account on a new machine until authorized by the user (however, this is unfortunately at times done via email, which as stated above is far from ideal). The way Zccount currently proposes to handle this is to either derive a reproducible unique identifier for each machine or if unable to, one will be generated to serve the same purpose (and as per adhering to the philosophy of diversity, this machine identifier will be altered for each service). For security reasons, the user should be able to request a listing of the devices associated with a service so that they can be revoked by the user should they expect any of them to become compromised, along with allowing the machine identifier itself to be regenerated.
The proposed method by Zccount for how a user will consents to a login on a new device through a synchronizing process where a device with the account logged in (presumably a mobile device in most cases) will begin generating time-based one-time passwords15 (TOTPs) to be entered into onto the other device correctly X times in a row (where X will either be standardized or determined by the vendor) to prove that the user is in fact the one logging into the account. The also provides the added security should their accounts become compromised since it would inhibit the attacker for logging in on a new device.
Accessibility
I am not referring to Zccount's accessibility to the disabled here (which is definitely important, but due to it's core principle of being Automatic it already is), but rather how accessible the Zccount system is to everyone currently using the username / password scheme. Ideally, Zccount should be usable to anyone that is currently able to use a username and password to log in to their accounts. While this may appear obvious, many of the recent systems that try to tackle the user authentication problem have been heavily relying on either the existence of biometrics or audio / visual inputs (e.g. cameras and microphones). These technologies work great for 2FA, due to the fact that only recent devices have these features, others like older laptops and a plurality of desktops would be left unable to use Zccount with adding the appropriate hardware (and also adds in an unneeded layer of breaching the privacy of the user by requiring they provide their face, voice, fingerprints, etc to identify themselves to a service). For this reason, any implementation or proposal for Zccount should assume the least amount of hardware possible so the maximum audience of users is reachable.
Automatic
This principle is not so needed from a security standpoint, but rather from the perspective of user experience and adaptability which is crucial in ensuring the success of Zccount being used in the "real world". The method Zccount proposes to allow for automated user authentication is by generating the identifier and verifier (which is analogous to the username and password in the old model). When an account is made with Zccount, the user identifier, verifier, and the machine identifier triad will be generated and will again be done for each service. The way Zccount proposes to solve the issue of authenticating with the server is to send it's user and machine identifier to the server over a secure connection (i.e. HTTPS and not HTTP) and request the server to generate a verifier on it's end for the account along with an artificial neural network16 (ANN).
Taking a brief tangent away from the authentication process, I want to explain why ANNs are used here. While ANN's are not something associated with user authentication, what they are when taken outside of the context of machine learning is a function that approximates functions, e.g. when given a set of inputs it creates an approximate function that creates the expected output. A problem of ANNs in the machine learning space is that when applied continuously on the same set of inputs, it suffer from overfitting17 where it can supply the correct output for the inputs used for training, but for all other inputs the function doesn't work as expected (I won't explain why this is here since it is outside the scope of this paper so just take my word for it here). However, in this case we're going to abuse the properties of overfitting to suit our needs. We are going to take the ANN provided by the server (which can and should be a different / random architecture for each user) and use our local verifier as the input to train the ANN to output the server's verifier. Once trained, the client will convert store the architecture and weights of the ANN to send to the server and store locally. To maximize security, multiple different ANNs can be sent to the user to train against (and even better, supply a different verifier for each ANN), so the server can randomly send a network to the user to test against for authentication. This way the server never sees the user's verifier, yet can verify the authenticity of the user.
Desired Features
While Zccount should not deviate from it's core principles, there are non-essentials features it ought to have to fully replace the niceties that users have come to expect from the current user authentication model. As of right now, the core principles of Zccount allow for the subjective user experience of visiting to be automatically having an account created where the account is bound to the user's machine and using a near-impossible verifier to brute-force along with an identifier that cannot be used to track the user across different sites, all without any action from the user. The only thing the service would need now for the account is application specific information about the user. While this is definitely an improve from the default security a plurality of users begin with, there's some features that may be desired.
Recoverability
In the current email / username / password scheme a user can reset their password for their account when any combination of the three are lost or forgotten by either sending an email, asking for personal information only the user would know that was collected prior (e.g. phone number, social security number, etc), or answering security questions. Each of these approaches has their own faults (most of which described above). While Zccount can cope with this in a situation where the user has logged into at least one other device prior and has access to it (via re-syncing the account as described in Consent), but there's no good and secure way to do this when only one device is associated with the user's account. This can be remedied by requesting the server generate a recovery key (similar to the backup codes provided through 2FA) prior and to supply them to prove authenticity (as a side note, these keys should be able to be revoked and regenerated at any point if it is expected they have been compromised). While in keeping up with the "more security by default" philosophy it may seem odd that recoverability is not something provided by default, it is in fact more secure to have recoverability as an opt-in feature rather than an opt-out. While recoverability is convenient it opens another security hole in the account that could be exploited and not including it renders attackers just as powerless to enter the account as the user if the credentials are lost. However, losing credentials should be nowhere near as easy with Zccount because they are generated automatically by Zccount where no action is issued by the user, so as long as Zccount is working on the user's device the credentials should be there as well.
Design Flaws
While the current proposals for Zccount eliminate many of issues users face in the user authentication process, it is not without it's own drawbacks and flaws. This is hopefully where others can come in to suggest amendments to the Zccount proposal to rectify these issues.
Viruses / Malware
No device is every completely safe from viruses and malware. The current model is vulnerable to attacks where either of these two can attempt to read and/or corrupt the locally stored values on the user's machine for Zccount. The worst case scenarios here is that the attacker finds a way to reverse-engineer which credentials match up to which service and attempt to use them to hijack a user's account or by corrupting the data it can lock a user out of their accounts (which can be minimized by using methods described in Consent and Recoverability). While other measures should be taken to prevent this and it is not directly within the scope of problems Zccount tries to solve, the side-effect is drastic enough that prevention measures should be considered.
Conclusion
Users deserve a better user experience than the one provided to them by online services. The current user authentication system adheres to a "blame the consumer" ideology where if a user is not knowledgeable of the actions needed to be taken on their part to ensure security, they are left unprotected and defenseless against attackers while under the belief their assets are secure. We have the available technology to provide a better solution, regardless of whether that solution is Zccount or something else, so let's make a change and provide users the security they deserve.