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Comment: Implant with a 666-bit keypair (Score 1) 49 49

You could implant a cryptographic radio transponder with a 666-bit keypair in people's forehead or right hand. The plus side is that it'd combine the positive aspects of a "something you have" transponder with biometrics' resistance to loss or theft. The minus side is protests from Christians who think it's the mark of the Beast mentioned in the revelation to John of Patmos.

* Actual theft, not copying.

Comment: Type 4 UUIDs (Score 1) 226 226

The combination of time (the UUID can be time boxed), activity (a successful login nullifies the UUID), and possession (control of the account's registered email address)

My concern is how to keep someone between your server and the subscriber's MUA from compromising "possession", or how to establish "possession" the first time.

Assuming the coders didn't decide to come up with their own GUID generation algorithm that is easily reverse engineered and seeded

I just use a PRNG. If I need it as a GUID, I request 120 random bits and format them as a type 4 UUID. Is that good enough?

Comment: Re:Responses (Score 1) 226 226

Or to put it shorter: "Passwords and password reset codes go in separate fields."

I've implemented a similar system that keeps the hashed password and the one-time-use code in separate fields of the user table. I just wondered if there was any good way to protect the "login ticket" (the mail containing the one-time-use code) from interception in the 24 hours between when it is sent and the expiration time that we store.

Comment: It's to confirm control of your e-mail address (Score 1) 226 226

In the message the portal not only assigned my username, but it also listed a temporary password that's good for 30 days! All of this transmitted cleartext.

This use of a one-time, soon-expiring autogenerated password is common in flows that include the step "To reset your password, confirm your e-mail address" or "To opt in to e-mail notifications, confirm your e-mail address". Is there an alternative, other than to either A. mail all customers a second factor of authentication used to reset a password, or B. require all customers to subscribe to mobile phone service with unlimited texting to receive resets through SMS?

Comment: Security theater questions (Score 2) 226 226

Send an e-mail with a verification URL

How do you encrypt this unique verification URL on its way to the subscriber to your service?

security questions

I'm sorry; I misread this as "security theater questions". See "The Curse of the Secret Question" by Bruce Schneier and "Wish-It-Was Two Factor" by Alex Papadimoulis.

Comment: Facebook defeats security theater questions (Score 1) 226 226

The questions we ask are not something that would normally be found in a users inbox

A lot of time, the answers to security theater questions are things that would be in a user's Facebook timeline, such as the name of the middle school that the user attended.

Comment: Not 100% of Internet users have unlimited SMS (Score 1) 226 226

If you want a bit more security than this you could do something like text the user the token instead of baking it into the URL.

But how do you send a text to the number "I don't have a cell phone" or to a land line? I tried to send the code to a land line on a couple sites and got "Unsupported carrier".

Comment: It is "a random hash" (Score 1) 226 226

and send them an email with a link (containing a random hash that's indexed to that user in the DB) to verify the email address

But how would you encrypt "a random hash" on its way to the e-mail recipient?

Why would you need to generate a password for them, especially if you're going to email it plaintext and make them change it anyway?

Because this one-time random password serves precisely the same purpose as "a random hash" that you mention.

Comment: Cellular explained with a car analogy (Score 1) 84 84

What's the barrier to choosing a different brand of car?

In this analogy, there are several road owners, and each road rejects all cars that lack a subscription to that road's owner. This means each of the major road owners owns a set of parallel roads that serve each destination.

  • Roaming: Some road owners have negotiated deals with other road owners to allow cars that subscribe to those road owners.
  • Lack of coverage: Some road owners don't own a road that goes where you need.
  • Carrier locking: Inability to subscribe a car to any road owners other than the one that sold the car.
  • Family plan: Deep discounts for registering more than one car with the same road owner.
  • Spectrum crunch: Limited real estate for building new roads.
  • Wi-Fi data offloading: Rat running through parking lots and private drives.
  • Wi-Fi Sense: Your car shares a map of your rat runs on social media.

But if you meant literal cars, I don't know what barrier the other AC was referring to either.

Memory fault - where am I?