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55

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 ...


30

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 ...


21

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.


10

Using the old martial art of Google-Fu I managed to find these two comments on the first and second page after providing the search parameters: "Bitlocker hibernation". From the Microsoft website: What are the implications of using the sleep or hibernate power management options? BitLocker on operating system drives in its basic configuration (...


9

Unlikely. It's AES-CBC-128, so there's no chance of you cracking the key. There are a few tools (e.g. Volatility, or Elcomsoft's forensics suite) that can recover the master key from a system memory dump, but that only works if the drive is already mounted and unlocked.


9

Boot Process Secure Boot There are quite a few steps to booting Windows 8. Now secure boot in general means that the boot loader is only run if its integrity can be checked. In this case, if enabled, the UEFI is started before anything else and checks that the boot loader is signed by a trusted Certificate Authority. For an operating system generally ...


6

Disk encryption requires the host to keep or derive a master key which is kept somewhere in memory so that's your biggest issue. I've implemented aspects of the SafeNet ProtectFile product and other smart-card stacks so I'm intimately aware of the challenges. Don't for a minute think you have any real security. There are "digital forensic devices" that ...


6

There is currently only one cold boot attack I know of that works against bitlocker. However it would need to be executed seconds after the computer has been turned off (it can be extended to minutes if the DRAM modules are cooled down significantly) but due to the timeframe of execution it's rather implausible. Bitlocker is secure as long as your machine is ...


5

Yeah. There are many alternative to Truecrypt and BitLocker that you can find in link below: http://alternativeto.net/software/truecrypt/ However I software that meet you prerequisites are DiskCrypter and FreeOTFE(not supported anymore). P.S. there is no guarantee that they are backdoor free!


5

BitLocker encrypts the drive using a "volume master key", which is never placed directly in persistent storage anywhere. One or more "key protectors" are present in the volume metadata, each one of which provides a way to obtain the VMK. For the PIN/Password-based protectors, the password is passed through a very slow key derivation function (something like ...


5

The attack you outline is a fundamental problem for all types of encryption: If you want to use a password as the (source of) the encryption key, the password must have as much entropy as the desired encryption strength, otherwise you are vulnerable to offline brute-forcing. So yes, if Bitlocker just used the password you entered as the (source of) the key, ...


5

Any time you install software from a vendor or project you are placing trust in that vendor or project not to have placed malicious code in there and also to have done a reasonable job of securing it. Some people may suggest that open source is the answer to this, but without repeatable builds and a full source code audit done by someone you trust, there's ...


4

It's not possible to find arbitrary digits of the pin. It's an all-or-nothing deal. Assuming a numeric pin, there are 10,000,000 possible combinations. Depending on the implementation of the key derivation algorithm, it may take up to ~1s per attempt - that's roughly 58 days before you have a 50% chance of hitting the correct key, with 116 days (almost 4 ...


4

After conducting extensive research on the Bitlocker platform, I believe I can answer my own question. Key reference: Bitlocker Drive Encryption Technical Overview In our default setup (at least on MS Surface Pro 3), Bitlocker, UEFI and Secure Boot are on. There is TPM 2.0 enabled. The UEFI is not password protected, and the boot order allows USB before ...


4

No, it's not secure. You're vulnerable to: Cold boot attacks (freeze memory and extract the contents, get BitLocker encryption keys and all your other sensitive data) DMA attacks via FireWire, CardBus, ExpressCard, Thunderbolt, etc. Installation of a physical keylogger (many laptop keyboards can be easily removed) or backdoor hardware. In general, if an ...


4

First off, you should go type "how bitlocker works" into google and read a few articles. You will probably learn the answer to your question (and a bunch more interesting things besides!). If you want a quick answer, I found an article by Microsoft that says: During the startup process, the TPM releases the key that unlocks the encrypted partition only ...


3

Prevent someone from gaining physical access to your system while it's running. Seriously, the linked tool works by searching through an image of your system's memory for the key for the encrypted volume and using it to decrypt the encrypted volume. The only way to prevent this is to make sure an attacker can't read the memory of a running (or suspended or ...


3

I don't know of independent security audits, but your questions 1-4 are relatively easily answered from official sources. I would have no reason to distrust the official sources on those matters. The quick answers are: Yes, the TPM is tamper-proof hardware which stores and protects your key. This is manufacturer dependent but most use an exponential ...


3

DPAPI functions basically two ways, either the info you're protecting is encrypted at a machine level, or a user level. If you're running as a service, you need to use machine level. If your running under a user, you can use the user level. The difference is that for the user level, the user's password basically provides the encryption for the data you pass ...


3

Okay, so, after some more searching I solved my problem: Bitlocker does allow you to use an actual password (but they call it a PIN) - can't be more than 20 characters, but that's still pretty good. RUN > gpedit.msc Select: Administrative Templates > Windows Components > Bitlocker Drive Encryption > Operating System Drives Double click "Require ...


2

Bitlocker is vulnerable to much the same attack. This paper describes an attack against the PIN: "At the next boot, the MBR boot loader loads this file and transfers control to it. A fake BitLocker prompt is displayed (see figure 1); the entered PIN is stored in the NTFS partition, the original MBR is restored and the system rebooted. Later, the entered PIN ...


2

Best practice depends on what you are worried about. The danger of Sleep mode is that your key is still in memory, and can be extracted by an attacker with that expertise. Hibernation significantly reduces that risk in all scenarios. As Lucas Kauffman's answer indicates, using the advanced BitLocker implementation modes provides extra security, as well as ...


2

This is not what Bitlocker is for. Full Disk Encryption (FDE) tools like Bitlocker are only meant to protect against off-line attacks. This is where the computer's operating system is not running. Examples might be if the disk is removed and mounted in another computer, or if the computer is booted from a LiveCD or similar. When the OS is running - ...


2

What kind of attack are you trying to protect yourself from? Assuming your only concern is that the data on your lost/stolen laptop will not be readable, then it is OK to carry the recovery key with you. Generally people are very good at securing their wallets, it should be "safe" to keep it on a piece of paper in your wallet. If you're concerned about ...


2

There is also the "Evil Maid" attack that could, in theory be used against any software disk encryption, as the boot loader needs to still be unencrypted. See Bruce Schneier's article about it from 2009. http://www.schneier.com/blog/archives/2009/10/evil_maid_attac.html The general gist of the "Evil Maid" attack is that someone gets ahold of your laptop for ...


2

Thankfully no. The actual keys used to encrypt the data volume are randomly generated securely anyway. These keys are normally stored in the TPM and will be released when the TPM's integrity check is done on pre-boot components and settings. Note that the TPM key has nothing to do with the Windows user account and password (you can always add and remove ...


2

In addition to Polynomial's answer it's worth noting that the network interfaces will still be up and active and any access through that route (shares, remote management services etc.) may permit access to stored data regardless of screen locking. Either remote network sessions, or someone plugging in a device to your network ports could provide a surprising ...


2

Why not both? If you enable BitLocker to without a TPM (group policy editor), then tell it to use "TPMAndPINAndStartupKey", it should require both the file-based startup key and the PIN (which, if you enable "Enhanced PINs" in group policy editor, can be actual passphrases). Also, in either case, I wouldn't worry too much about brute forcing. BitLocker has ...



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