4 ms·
Depending on the settings, the phone could: * Wipe after 10 unsuccesful PIN attempts * Be configured with a 6 digit numeric PIN code * Be configured with
by 0x0 11y ago
Depending on the settings, the phone could:
* Wipe after 10 unsuccesful PIN attempts
* Be configured with a 6 digit numeric PIN code
* Be configured with an unlimited alphanumeric password
* Exponentially increase delay between PIN attempts after
unsuccessful entry - for example 3 attempts in 3 seconds,
next attempt after 10 seconds, next attempt after 60
seconds, next attempt after 4 hours, next attempt after
24 hours, next attempt after a week, next attempt in a
year (making up numbers to prove a point)
- wingerlang 11y agoMaybe fixed now, but there was someone who got around the 10 unsuccessful (an perhaps the last one as well) by shutting the device off after an attempt was failed (like 0.001ms, not manually)
- eridius 11y agoBy "shutting it off" you mean they inserted themselves in between the battery and device and instantly cut power at the right time. Not something that you can easily do to an arbitrary device (especially if you have to give the device back). And I don't know for sure, but I feel like that one was fixed at some point. Edit: Yep, superuser2 links to the CVE: https://news.ycombinator.com/item?id=10423257 https://news.ycombinator.com/item?id=10423257, https://cve.mitre.org/cgi-bin/cvename.cgi?name=CVE-2014-4451 https://cve.mitre.org/cgi-bin/cvename.cgi?name=CVE-2014-4451
- beeboop 11y agoThese are mostly moot points. They don't have robots trying millions of passwords on phones. They make an image of the phone's memory and brute force it elsewhere. Even a 6 digit code would be cracked in seconds, at most.
- deleted 11y ago[deleted]
- superuser2 11y agoFalse. The PIN is an input to the onboard HSM, which holds the actual key. The HSM itself enforces rate limiting and, if you have the right setting enabled, wipes its contents after N bad PINs.
- ars 11y agoSo impossible really means impractical. That HSM is still just a physical machine, and it can be, with difficulty, modified or copied. To be impossible it would have to be mathematically impossible (or at least not within human time scales).
- beeboop 11y agoOr emulated, which I am sure is not difficult for NSA.
- ars 11y agoTo emulate you need to copy first.
- zyx321 11y agoYes. Really, REALLY impractical. "Disassemble phone, desolder security module, dissolve the outer layers in hydrochloric acid, cut the silicon into 16nm slices, scan each layer with an electron microscope" impractical.
- marvin 11y ago"In a vaccuum while avoiding all the traps that the HSM maker designed, each of which will physically destroy the key if triggered".
- chris_va 11y agoPhysically interfering with the delay/wipe mechanism should be possible. You only have to build the solution once. I can see that this makes it much harder up front, but eventually this too will get cracked.
- 2bitencryption 11y agoNot true -- on newer iPhones this is actually done on dedicated hardware that enforces these limits. It's actually really impressive.
- comex 11y agoWell, given that the Secure Enclave is a processor, I suspect the relevant statement in the whitepaper just means that it's done by software on the SEP rather than the main processor, not that it's done purely by hardware. I could be wrong. But if I'm right, note that the SEP will take firmware upgrades signed with Apple's key, same as the main processor.