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Flaws in deleted keybase app kept1/1/2023 ![]() ![]()
They used prepaid plans as they could refill accounts using cash at physical phone stores or check cashing stores because they don't have a computer or bank account. They frequently changed phone numbers due to: "crazy" ex, owes money to scary people, owes child/alimony support, owes the government, commits crimes and uses frequent burners, did jail time, or the #1 reason out of minutes and no money to put on the prepaid plan. This leads to a very unstable life where money really is scarce. ![]() They came from low income backgrounds and were poorly educated. I spent a lot of time with guys in late teens and 20's, mainly black and hispanic kids looking to make some decent side money. FLAWS IN DELETED KEYBASE APP KEPT MANUALI come from a family business that used a lot of manual labor from the local neighborhood here in south Queens, NYC. What income bracket is your circle? Just going to reminisce a bit here. > I guess I don't have "dozens of contacts", but getting a new phone/resetting a phone isn't really that common of a thing in my circle. Again this requires support in the chat protocol itself. A PAKE lets two parties agree a key based on knowing some relatively weak secret, Mallory can try to guess but only gets one chance each time this is done and failure is detectable by Alice and/or Bob. I _think_ if Alice and Bob know a weak human secret they can do something here with a Balanced PAKE. Mallory can continue to relay messages, but they are now passive and don't learn anything beyond traffic analysis or have any ability to tamper with the messages.īut chances are Alice and Bob don't have such a secret (and of course they can't use the potentially MITM'd channel to agree one) This only requires updating the protocol to allow such a secret to be introduced. If Alice and Bob know a good secret (say a 128-bit AES key) then they can definitely just use that secret to protect their communications against the MITM. The _protocol_ can be arranged to help you do this, but yes just asking a challenge question inline doesn't protect against a MITM. Note, shuffling a deck isn't a great source of randomness, but you could use dice or a computer to generate the key - then map it to a sequence of cards.] ![]() Or add add a few checksum bits and use half a deck (26 cards). You could represent a ~128 bit key as a sequence of ~23 random cards. [ed: for example there are 52 cards in a normal deck of cards, meaning each card encodes about 5.7 bits(2^5=32,2^6=64). Other than that - I've not really heard of gpg keys or ssh keys being brute forced - but that may be because by the point you gain access to the (encrypted) private key - you already have access to everything else? FLAWS IN DELETED KEYBASE APP KEPT CODEI suppose the pgp/ssh model of secure device holding the master key plus the ability to backup (eg qr code printout in a safe).Īn approximation for phones would be a random key locked in the device with a pin, an the ability to transfer and backup keys as you mention. Having it be a real approximation to random doesn't help. 128 bits (say) is a lot of data to memorize. Yeah, "cryptographically secure" and "something you remember" doesn't mix well. However it doesn't have anything to do with the actual security flaw (if we want to call it that, it's really more of a UX / messaging problem) being discussed. The quote you linked is relevant because it means that you can't simply ignore this problem resets are fairly common, common enough that you can't just delete the key-loser's account (for example). Unlike real the time someone is interested in your TOFU conversation, they can't break in. It's more like TADA - Trust After Device Additions.1 This is a real, not articifical, problem, as it it creates an opportunity for malicious introductions into pre-existing conversation. So to call most E2E chat systems TOFU is far too generous. FLAWS IN DELETED KEYBASE APP KEPT ANDROIDHey - do you have Caroline's current address? Gonna surprise her while I'm in SF.Īlice: Bad call, Android 4 life! Yeah 555 Cozy Street. Let's exchange safety numbers at RWC 2020. Alice and Bob have been in contact for years, having long ago TOFU'ed.Įve simply makes it look to Alice that Bob bought a new phone:Īlice: Yo Bob! Looks like you got new safety numbers.īob (Eve): Yeah, I got the iPhone XS, nice phone, I'm really happy with it. ![]() Let's say Eve wants to break into Alice and Bob's existing conversation, and can get in the middle between them. ![]()
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