I was sitting in a planning meeting with a client recently in which we were discussing ways of protecting end-user machines, especially laptops that were in and out of the office. The previous convention relied on BIOS locks that were proprietary to the hardware manufacturer, and required the end user to either enter two passwords or swipe their fingerprint on a sensor. As the company planned to migrate away from the dedicated hardware provider and toward a CYOD (Choose Your Own Device) type of environment this would no longer be a viable solution.
As the discussion started about what they were planning to use to provide a second layer of protection from unauthorized access to systems, I asked if the company was still intending to use BitLocker to encrypt the hard drives for these machines. When it was confirmed that they would, I presented the hardware agnostic solution: adding a PIN (Personal Identification Number) to BitLocker.
BitLocker is a disk encryption tool that was introduced with Windows Vista, and has been greatly improved upon since. It ties in to the TPM (Trusted Platform Module) in your computer (included mostly in Enterprise-class systems) and prevents protected hard drives from being hacked. Most people configure it and leave it there… which means that it is ‘married’ to the physical computer with the TPM chip. However there are a few additions you can add.
Authentication has not changed much in the last few thousand years. It is usually based on a combination of something you have and something you know. Beyond that is it just levels of complexity and degrees of encryption. So our TPM chip is something we have… but assuming the hard drive is in the computer, they go together. So we need another way of protecting our data. Smart cards and tokens are great, but they can be stolen or lost… and you have to have to implement the infrastructure with a cost (although with AuthAnvil from ScorpionSoft the cost is low and it is relatively easy to do).
Passwords work great… as long as you make them complex enough that they are difficult to hack, and ensure people change them often enough to stymie hackers… and don’t write them down, and so on. However even with all of that, operating system passwords are still going to be reasonably easy to crack – to the knowledgeable and determined. Hardware level passwords, on the other hand, are a different beast altogether. The advent of TPM technology (and its inclusion in most enterprise-grade computer hardware) means that an encryption tied to the TPM will be more secure… and by adding a PIN to it makes it even more so. Even though the default setting in Windows is to not allow passwords or PINs on local drives, it is easy enough to enable.
1. Open the Group Policy Editor (gpedit.msc).
2. Expand Computer Configuration – Administrative Templates– Windows Components – BitLocker Drive Encryption – Operating System Drives
3. Right-click the policy called Require additional authentication at startup and click Edit.
4. Select the Enabled radio button.
5. Select the drop-down Configure TPM startup PIN: and click Require startup PIN with TPM.
At this point, when you enable BitLocker, you (or your user) will be prompted to enter a PIN when enabling BitLocker.
**NOTE: This policy will apply when enabling drives for the first time. A drive that is already encrypted will not fall into scope of this policy.
By the way, while I am demonstrating this on a local computer, it would be the same steps to apply to an Active Directory GPO. That is what my client will end up doing for their organization, thereby adding an extra layer of security to their mobile devices.