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Feb
13
awarded  Curious
Feb
12
comment Are there other roots of trust on my computer aside from these 46 root certificates?
Thanks Eric. It looks like the reason for the discrepancy is that Windows automatically updates the root certificate store as needed.
Feb
12
accepted Are there other roots of trust on my computer aside from these 46 root certificates?
Feb
12
comment Are there other roots of trust on my computer aside from these 46 root certificates?
I just confirmed this. Going to hongkongpost.gov.hk/index.html results in Hongkong Post Root CA1 added to the "Trusted Root Certification Authorities".
Feb
12
comment Are there other roots of trust on my computer aside from these 46 root certificates?
Can you tell me exactly where you found the Hong Kong Post office root certificate? I've checked on both my windows 7 and 8.1 machines and haven't found it.
Feb
12
revised Are there other roots of trust on my computer aside from these 46 root certificates?
added 76 characters in body
Feb
12
asked Are there other roots of trust on my computer aside from these 46 root certificates?
Feb
12
accepted Does a valid code signing certificate mean that an installer has not been tampered with in transit?
Feb
12
comment Does a valid code signing certificate mean that an installer has not been tampered with in transit?
I'm using a script to automate download and validation, so I suppose I could fairly easily assert that the publisher and chain of trust remain the same. I wonder how consistent the certificates used to sign code actually are from update to update.
Feb
11
awarded  Critic
Feb
11
comment Does a valid code signing certificate mean that an installer has not been tampered with in transit?
This answer seems to speak to TLS communications. The question is about signed files. Can you explain how this applies to the question?
Feb
11
asked Does a valid code signing certificate mean that an installer has not been tampered with in transit?
Feb
7
awarded  Popular Question
Nov
27
comment Secure Boot on Microsoft Surface Pro 3 (or modern PCs)?
This question is related to your final question.
Nov
17
comment Accessing iPhone data without passcode - how difficult?
Can you give an example of how insecure boot could result in accessing user data without a passcode on modern iOS? Ostensibly, decrypting user data requires the passcode regardless of malicious boot code.
Nov
16
revised Accessing iPhone data without passcode - how difficult?
added 22 characters in body
Nov
16
awarded  Teacher
Nov
14
comment Accessing iPhone data without passcode - how difficult?
Interesting. It looks like a high-entropy key is derived algorithmically from, in part, the passcode. However, this is done in a separate chip containing and using a unique ID. This arrangement complicates performing an offline brute-force attack and limits the online attempt rate. See my answer for more details.
Nov
14
answered Accessing iPhone data without passcode - how difficult?
Nov
14
comment Accessing iPhone data without passcode - how difficult?
The second bullet surmises that the key can be algorithmically derived from the passcode. It seems plausible that instead, while the device is locked, a high-entropy key is stored only in a "trusted" area of hardware (a la bitlocker PIN+TPM), and that key is unlocked with the passcode. The premise in that case is that the key is much more difficult to exfiltrate from the "trusted" area of hardware than brute-forcing the 4-digit password after dumping the plain-old flash.