I just got my Mk4 last week, it's my first ColdCard. I've been having a little fun with it before I set up for coldish storage. I'm starting to become attached to it however, I may need another for that original purpose. An Mk3 would probably suit just fine, and I could use the Mk4 as my "daily driver."
I don't think Coldcard Mk3 is suitable for that, because it was exploited like I wrote before, and if your device is running outdated secure element ATECC608A than it makes it even less secure.Check what version of bootloader is in your device but if you have v2.0.0 than your device is not safe from this exploit.
Read more information about that:
https://threadreaderapp.com/thread/1377362927729082368.html
Yeah, I've read about that attack vector, but it seems like any hardware wallet could be vulnerable to the same attack. Currently I'm using a Trezor and we all know it's also vulnerable to a similar physical attack. As you also mentioned in your post the updated bootloaders mitigate the possibility and I imagine (like a Trezor) a Bip39 passphrase would also mitigate this issue. Not to mention, if I was to use the Mk3 for coldish storage, they'll have to break into my gun safe before they can break into my hardware wallet.
The only advantages I see to the backup feature are quicker recoveries and cloning the ColdCard. I could see myself using it for cloning, but for securing my seed or as an alternative to paper? No way! I don't trust anything as much as a good old-fashioned paper backup, copied and stored securely in sperate places.
If you can please post some review and comparison between mk3 vs m4.I am interested to learn more about it and we may get more attention from mister Busy Nvk.
I wish I could, but I don't have an Mk3, this is my first ColdCard. I don't even own any OpenDimes, and that seems like a tragedy all on it's own.
Although it does seem silly to backup your 24-Word seed phrase with a 12-word phrase, lol.
It does sound extremely silly, and I don't trust sd cards for any long term storage, but I guess multiple copies mitigate the risks.I'm not sure. Digital media is a new technology, obviously. It may be archival but for how long? We won't know until we know. Maybe when the first Egyptians put ink to paper there was a "Dire Wolf" poopooing the idea and saying stupid shit like "that's never going to last, just chisel that shit in stone like a man."
