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73

The ANSSI, French government service in charge of IT security, has published a document providing brief advice to people having to travel abroad. Relevant here are the advisories concerning preparation before travel: Review the applicable company policy, Review destination country applicable laws, Prefer to use devices dedicated to travel (computers, ...


61

Two generic things you apparently have missed: In case of disk failure, having the data encrypted at rest solves the issue of having potentially sensitive data on a media you can't access any more. It makes disposing of faulty drives easier and cheaper (and it's one less problem) Full disk encryption also makes it harder for an attacker to retrieve data ...


58

In a word: sufficient. This is block-level encryption, so it is filesystem-independent. Ubuntu's transparent encryption is done through dm-crypt using LUKS as the key setup. The built-in default for cryptsetup versions before 1.6.0 is aes-cbc-essiv:sha256 with 256-bit keys. The default for 1.6.0 and after (released 14-Jan-2013) is aes-xts-plain64:sha256 ...


53

You’re misunderstanding what BitLocker is supposed to protect against. The goal of BitLocker is to protect your data from cold boot attacks (as explained in a Technet blog entry). When you unlock a volume protected by BitLocker, the system gains access to the keys necessary to decrypt the drive and behaves as if it was a regular drive. That is necessary to ...


47

Chip-based banking cards typically use a 4-digit PIN. It would take at most a few hours to try them all if the card didn't protect against brute force attempts. The card protects against brute force attempts by bricking itself after 3 consecutive failures. The adversary does not have access to a hash of the PIN (there are physical protections in the card ...


41

The main obstacle of a TrueCrypt fork is the non-standard TrueCrypt license. While the intention of the authors seemed to be to write a share-alike license similar in spirit to the GPL, the license has a few quite unorthodox passages which can be interpreted in a way which puts unreasonable conditions on a fork. These conditions prevented the Open Source ...


31

The advantages are limited, but there are nonetheless scenarios where encryption helps. In any scenario where the attacker obtains the password¹ (with lead pipe cryptography, or far more realistically by reading the unlock pattern on the screen or brute force on the PIN), there is clearly no advantage to full disk encryption. So how could the attacker ...


29

For the determined attacker setup: The encryption technology used in Android 3 is dm-crypt. The relevant part here is the following: encryption uses a symmetric key, which is derived from the password/PIN typed by the user; the derivation parameters are stored in a LUKS-formatted block on the device itself. Password derivation is salted and uses many ...


29

A smart card works by keeping a secret hidden and answering a challenge that proves it has the secret. It, theoretically, should never reveal that secret to anyone and it should be unrecoverable. There are some technical ways you might be able to get around it, but most of them are destructive to the card. This means you know if your smartcard has been ...


28

Your first question is really a legal one, and you seem to be assuming two things: The attacker is a government of some sort. That government actually respects citizen privacy and requires some sort of reasonable suspicion before it can force people to give up encryption keys. Neither of those assumptions are necessarily true. For all you know, some ...


21

One benefit of full-disk encryption is that it makes wiping the flash storage very fast. All of the data stored on the device is stored encrypted under a particular encryption key K. The system also stores an encryption of K under the user's PIN. To wipe the entire drive, all you have to do is wipe the spot that stores the encryption of K (which is just ...


21

There are a number of defenses you can use to help prevent and recover from theft. The first thing you should look into is full-disk encryption, e.g. LUKS, TrueCrypt, or PGP. This will prevent an attacker from reading any data on the disk, even if they steal the hardware. You will need to enter the password at boot, though, so for unattended remote hardware ...


20

It's (theoretically) harder to duplicate a Smart Card. You can duplicate a USB drive easily. If I steal both, you are equally in trouble, but if I steal the USB, duplicate it, then replace it without you knowing, then you are in trouble and you don't know it.


19

Before you read all this, remember that this technique is at least 5 years old -- it's probably much easier by now (see the other answers). (But it sure was fun to figure this all out.) I did this a few years ago with Fedora 10 and Windows Vista to demonstrate how all the intricacies fit together. It was a bit involved (mostly because Windows Vista doesn't ...


19

How secure is the data in a encrypted NTFS folder on Windows (XP, 7)? What is EFS? Folders on NTFS are encrypted with a specalized subset of NTFS called Encrypting File System(EFS). EFS is a file level encryption within NTFS. The folder is actually a specalized type of file which applies the same key to all files within the folder. NTFS on disk format ...


19

In a data center, disk encryption can be useful for handling old disks: when a disk fails, you can simply discard (recycle) it, because the data it may still contain is encrypted and cannot be recovered without the corresponding key (this assumes that the server has the encryption key somewhere on its "system" disk -- or some other device -- and that the ...


18

I would still choose TrueCrypt for a matter of trust and the "many eyes" theory: After the "TrueCrypt scandal" everyone started looking at the source for backdoors. The TrueCrypt audit finished on April 2, 2015. They found low-risk vulnerabilities, including some that affect the bootloader full-disk-encryption feature, though there is no evidence of ...


18

You're wrong in your assumptions. There are many legal jurisdictions where you can be required to produce passwords for encrypted data on suspicion, rather than proof, that the data may be relevant to a criminal investigation. If you don't provide your password, you can be jailed. But if there's no encrypted volume visible, they don't know to do it. For ...


17

The short answer is this: We have no idea, probably none. It might protect against stolen backups. But that assumes Amazon even makes backups. That seems very unlikely. If they did, why couldn't they recover data from their last S3 data loss? It's much cheaper and more efficient just to use multiple live copies. Also, Amazon would need the keys on every ...


17

A useful and practical guide to securing information devices when crossing borders is provided by the Canadian Bar Association here. I would not say the U.S. border is the only one of concern, others such as China might eventually become similarly aggressive (though I've seen little sign of that to date). The guide echos many of the points made in other ...


16

The best way to protect against that type of border search is actually not to have anything suspicious on the hardware you take through the custom. Using encryption technology will most likely raise suspicion in the first place. Refusing to provide the necessary codes can, in some places, leads to the hardware being confiscated or even to you being ...


15

Modern research seems to indicate that performing a single zero-pass of a hard drive is sufficient for most data dispositions. In which case, no, performing a file or partition encryption would not be faster. Except in the case of hardware accelerated encryption (such as the newer Intel i series processors) encryption speed is CPU bound, whereas a single ...


14

The standard approach is to fill the USB ports with epoxy resin. Of course, this must be combined with similar approaches to seal the case, so the attacker can't get in via the PCI bus, etc. Note that even if you do this, law 3 still applies: if a bad guy has unrestricted physical access to your computer, it's not your computer anymore. EDIT: reflecting ...


14

If the decryption key is stored in plain on the very same media as the encrypted data, then the encryption is pointless. If you have a set of rules, which require data to be encrypted, but permit storing the key in plain on the very same media, then the rules are flawed. If you ever face such a flawed set of rules, you should point out the flaw. If the key ...


13

A quick calculation: First my assumptions: I assume the attacker has $1,000,000 to spend over the course of two years. He's using standard graphics cards, and pays 10ct/kWh. I assume that the KDF consists of 2*n SHA256 invocations, where n is the iteration count, and can be implemented with similar efficiency on graphics cards as plain SHA256. 1 A ...


13

Full disk encryption is the most common one used. The cost would depend on the time which needs to be implemented by the IT department ontop of normal laptop staging. However in my experience FDE is a must for any organization taking its security serious. Aside from that there are also some really anti-forensic tools, I remember a talk at Brucon where one ...


12

I have two solutions. Both require Full Disk Encryption (FDE). First Solution Credit to Bruce Schneier. Just before leaving home, create a second key. Type it with your forehead, a cat or dog, just so it's random and not possible to remember. Send the second key to a trusted person, preferably someone with a privileged relationship, i.e. lawyer, ...



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