Hope this isn’t a repeated submission. Funny how they’re trying to deflect blame after they tried to change the EULA post breach.
Hope this isn’t a repeated submission. Funny how they’re trying to deflect blame after they tried to change the EULA post breach.
This wasn’t a brute force attack, though. Even if they had brute force detection, which I’m not sure if they don’t or not, that would have done nothing to help this situation as nothing was brute forced in the way that would have been detected. The attempts were spread out over months using bots that were local to the last good login location. That’s the primary issue here. The logins looked legitimate. It wasn’t until after the exposure that they knew it wasn’t and that was because of other signals that 23andMe obviously had in place (I’m guessing usage patterns or automation detection).
Of course this is not a brute force attack, credentials stuffing is different from bruteforcing and I am well aware of it. What I am saying is that the “lockout period” or the rate limiting (useful against brute force attacks) for logins are both security measures that are sometimes demanded from companies. However, even in the case of bruteforcing, it’s the user who picks a “brute-forceable” password. A 100 character password with numbers, letters, symbols and capital letters is essentially not possible to be bruteforced. The industry recognized however that it’s the responsibility of organizations to implement protections from bruteforcing, even though users can already “protect themselves”. So, why would it be different in the case of credentials stuffing? Of course, users can “protect themselves” by using unique passwords, but I still think that it’s the responsibility of the company to implement appropriate controls against this attack, in the same exact way that it’s their responsibility to implement a rate-limiting on logins or a lockout after N failed attempts. In case of stuffing attacks, MFA is the main control that should simply be enforced or at the very least required (e.g., via email - which is weak but better than nothing) when any new pattern in a login emerges (new device, for example). 23andMe failed to implement this, and blaming users is the same as blaming users for having their passwords bruteforced, when no rate-limiting, lockout period, complexity requirements etc. are implemented.
So forced MFA is the only way to prevent what happened? That’s basically what you’re saying, right?
Their other mechanisms would prevent credential stuffing (e.g., rate limits, comparing login locations) so how was this still successful?
Yes, forced mfa (where forced means every user is required to configure it) is the most effective way. Other countermeasures can be effective, depending on how they are implemented and how the attackers carry out the attack. Rate limiting for example depends on arbitrary thresholds that attackers can bypass by slowing down and spreading the logins over multiple IPs. Other things you can do is preventing bots to access the system (captcha and similar - this is usually a service from CDNs), which can be also bypassed by farms and in some cases clever scripting. Login location detection is only useful if you can ask MFA afterwards and if it is combined with a solid device fingerprinting.
My guess in what went wrong in this case is that attackers spread the attack very nicely (rate limiting ineffective) and the mechanism to detect suspicious logins (country etc.) was too basic, and took into account too few and too generic data. Again, all these measures are only effective against dumb attackers. MFA (at most paired with strong device fingerprinting) is the only effective way there is, that’s why it’s on them to enforce, not offer, 2fa. They need to prevent the attack, not let just users take this decision.