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With Rising Database Breaches, Two-Factor Authentication Also At Risk (hackaday.com)
Two-factor authentication "protects from an attacker listening in right now," writes Slashdot reader szczys, "but in many case a database breach will negate the protections of two-factor." Hackaday reports:
To fake an app-based 2FA query, someone has to know your TOTP password. That's all, and that's relatively easy. And in the event that the TOTP-key database gets compromised, the bad hackers will know everyone's TOTP keys.
How did this come to pass? In the old days, there was a physical dongle made by RSA that generated pseudorandom numbers in hardware. The secret key was stored in the dongle's flash memory, and the device was shipped with it installed. This was pretty plausibly "something you had" even though it was based on a secret number embedded in silicon. (More like "something you don't know?") The app authenticators are doing something very similar, even though it's all on your computer and the secret is stored somewhere on your hard drive or in your cell phone. The ease of finding this secret pushes it across the plausibility border into "something I know", at least for me. The original submission calls two-factor authentication "an enhancement to password security, but good password practices are far and away still the most important of security protocols." (Meaning complex and frequently-changed passwords.)
How did this come to pass? In the old days, there was a physical dongle made by RSA that generated pseudorandom numbers in hardware. The secret key was stored in the dongle's flash memory, and the device was shipped with it installed. This was pretty plausibly "something you had" even though it was based on a secret number embedded in silicon. (More like "something you don't know?") The app authenticators are doing something very similar, even though it's all on your computer and the secret is stored somewhere on your hard drive or in your cell phone. The ease of finding this secret pushes it across the plausibility border into "something I know", at least for me. The original submission calls two-factor authentication "an enhancement to password security, but good password practices are far and away still the most important of security protocols." (Meaning complex and frequently-changed passwords.)
One big problem with 2FA is that they can phished. U2F is the neat solution in this space (I'm not not affiliated with them, just impressed with it). It's a little hardware key that...
-not fooled by phishing .... Apple is a no-show thus far.
-each site just gets a big random number at registration, so no user tracking from U2F
-integrates SSL to resist MITM
-it's a free standard and the devices are cheap
-Chrome supports it, Firefox is now in beta. Microsoft has made noises about support.
Apple is
U2F https://en.wikipedia.org/wiki/...
FAQ: https://medium.com/@nparlante/...
I've wondered why no one creates a USB/bluetooth device for security that has the ability to encrypt data based on a private key stored on that device. Then there would be no need for a database of private keys (nothing to be compromised except the device itself). I imagine it to work like this:
A new device is manufactured and loaded with the private key. The manufacturer then deletes any record of the private key and loads the public key to a public database.
When you need to identify yourself, the website sends to data to your device for encryption. The data is encrypted by your device using your private key and returned to the sender. The website then decrypts the data with the public key. If it decrypts properly, then you are authenticated. The private key never leaves the device and the public database could be protected by a block chain to prevent tampering.
Thoughts?
One thing: the big TOTP-key database isn't on your phone or computer or RSA fob/dongle. It's on a server run by whatever service you're authenticating with. And it's that database that's most likely to be compromised. That's true even for the RSA dongles, the host still has to have a database of all the keys so they can validate the code you entered against what your dongle should've generated.
A better solution would be USB hardware-based 2FA using public-key cryptography, and those aren't too expensive. It's just that there's no big money to be made there, by their nature the dongles can't be a locked-in part of a proprietary system so the big vendors and their salespeople have little reason to push for them.