With MFA even if somebody has your password if they don't have your physical authenticator too then you're relatively safe.
With MFA even if somebody has your password if they don't have your physical authenticator too then you're relatively safe.
There are plenty of scenarios where MFA is more secure than just a strong password.
Most people use their phones most of the time now, meaning the MFA device is the same device they're using.
Of the people who aren't using a phone, how many are using a laptop with a built in keyboard? It's pretty obvious if you have a USB dongle hanging off your laptop.
If you're using a desktop, it's going to be in a relatively secure environment. Bluetooth probably doesn't even reach outside. No one's breaking into my house to plant a keylogger. And a wireless keyboard seems kind of niche for a desktop. It's not going to move, so you're just introducing latency, dropouts, and batteries into a place where they're not needed.
Long, random, unique passwords are phishing resistant. I don't know my passwords to most sites. My web browser generates and stores them, and only uses them if it's on the right site. This has been built in functionality for years, and ironically it's sites like banks that are most likely to disable auto fill and require weak, manual passwords.
> There are plenty of scenarios where MFA is more secure than just a strong password.
And how realistic are they? Or are they just highly specific scenarios where all the stars must align, and are almost never going to happen?
The point is also that you as an individual can make choices and assess risk. As a large service provider, you will always have people who reuse passwords, store them unencrypted, fall for phishing, etc. There is a percentage of users that will get their account compromised because of bad password handling which will cost you, and by enforcing MFA you can decrease that percentage, and if you mandate yubikeys or something similar the percentage will go to zero.
For a typical person, maybe, but for a tech-minded individual who understands security, data entropy and what /dev/random is?
And I don't see how MFA stops phishing - it can get you to enter a token like it can get you to enter a password.
I'm also looking at this from the perspective of an individual, not a service provider, so the activities of the greater percentage of users is of little interest to me.
That's why I qualified it with "certificate-based". The private key never leaves the device, ideally a yubikey-type device.
Except that phishing doesn't require the private key - it just needs to echo back the generated token. And even if that isn't possible, what stops it obtaining the session token that's sent back?
There's also the issue of how many sites actually use it, as well as how it handles the loss of or inability to access private keys etc. I generally see stuff like 'recovery keys' being a solution, but now you're just back to a password, just with extra steps.
Sure, you can probably come up with some non-HTTPS scheme that can address this, but I don't see any site actually doing this, so you're back to the unrealistic scenario.
If I were trying to phish someone, I wouldn't attack the public key crypto part, so how domains come into play during authentication doesn't matter. I'd just grab the "unencrypted" session token at the end of the exchange.
Even if you somehow protected the session token (sounds dubious), there's still plenty a phisher could do, since it has full MITM capability.
This is part of why MFA just to log in is a bad idea. It's much more sensible if you use it only for sensitive actions (e.g. changing password, authorizing a large transaction, etc.) that the user almost never does. But you need everyone to treat it that way, or users will think it's just normal to be asked to approve all the time.