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Undocumented Bypass in PGP Whole Disk Encryption
A non-mouse Coward writes "PGP Corporation's widely adopted Whole Disk Encryption product apparently has an encryption bypass feature that allows an encrypted drive to be accessed without the boot-up passphrase challenge dialog, leaving data in a vulnerable state if the drive is stolen when the bypass feature is enabled. The feature is also apparently not in the documentation that ships with the PGP product, nor the publicly available documentation on their website, but only mentioned briefly in the customer knowledge base. Jon Callas, CTO and CSO of PGP Corp., responded that this feature was required by unnamed customers and that competing products have similar functionality."
If you RTFA you'd see this feature is needed for anyone who remotely-boots their encrypted drive. The feature is not a backdoor - it has to be enabled by someone with cryptographic access to the drive, and it only works once per setting - reboot, and it's disabled. The only way this could be a security issue is if it's enabled, and before the drive boots up again, the drive is stolen. Features like this are needed, as without them, the drive is useless for remote management, and people won't use encryption, which is obviously far more insecure than having this feature and using it correctly.
RTFA or at least TFComments (though that might be difficult in your rush to be first post). As many have pointed out, to turn on the feature, you have to already get past the encryption. It's not a "backdoor" in any sense. Someone who doesn't already know the passphrase can't use it to get access to the drive. Plus, this feature is turned off by default so the user has to actively enable it. You enter the passphrase, reboot the computer and on THAT boot, it doesn't ask you for a passphrase. Next reboot it does.
This actually DOES sound like a very good feature and I would hope other products have it, too. Wish the editors would RTFA, too...
They do have access to the keys. That's the point.
They need to do unattended automated reboots of thousands of computers. These are enterprise customers.
They have the encryption key, and they want to apply security updates and reboot the computers. When the employees come to work in the morning, they expect the computers to be on and operational, as they left it.
If you don't use the feature, then it poses no risk. If you need to apply unattended updates to computers on a large scale, going to each computer and typing in the passphrase is not practical.
This is a non-issue, and a FUD article. You need to have UNLOCKED access to the encrypted volume to enable this feature.
Normal users using PGPDisk and not using this feature are at no greater risk for it existing.
-=Lothsahn=-
There is an inherent flaw with many of the commercial laptop full-disk encryption solutions out there. I have the most experience with Utimaco's Safeguard Easy, but I know many of the other big players have the same fault -
The software has a feature called "Pre-boot Authentication", by which the encryption software is loaded after the bios, but before the (generally Windows) operating system. The user's password is used to generate the decryption key, so theorhetically not even the NSA could decrypt the laptop without the user's password.
Here's the flaw - the software has a checkbox to disable Pre-boot authentication. What this does is generate a default user with a random password, and then store this random password obfuscated but in clear-text in the same disk area decryption software. When you talk to the sales-people, they sell this as a feature, in fact about half of Utimaco's customers (so I'm told) run it in this mode because the encryption becomes transparent and it is much less intrusive on the user. (Basically the disk is automatically decrypted each time the laptop is booted, but you have to have a valid Windows login to get in.) Buried in the help documentation are warnings "For security reasons, you should Never disable pre-boot authentication". So the engineers and the company know the weakness of disabling pre-boot authentication, but they don't tell their customers when they sell the software.
Today it seems to break into these laptops with pre-boot authentication disabled you would need somewhat sophisticated tools and techniques, basically the same tools and techniques people commonly use to "crack" commercial software today. But I'm guessing that it won't be very long before someone takes the time to build this crack and releases it, rendering the laptop encryption useless to anyone who can Google for "Utimaco Crack", etc. Basically all the crack would need to do is grab the default user's password off the disk and use or duplicate the decryption algorithms that are also in clear-text on the disk.
I've talked to a number of IT security folks, and basically it seems like most people trust the sales folks and don't understand that its basically impossible to have strong encryption without having the decryption key stored off the disk (like on a smart card, or in the brain of the user.)
Because he failed to read the article correctly.
There isn't a backdoor. If you encrypt your hard drive, then lose it, nobody can read it.
If on the other hand, if you've encrypted your boot disk, and you want to remotely reboot your machine, you're going to need someway to feed the password to it before it can bring up the OS (and the networking layer).
This feature allows you to store a password for 1 time use. Then you reboot the machine, and when it comes up, it reads the password and erases it.
It's a useful feature. Doesn't effect you if you don't use it. Even if you do use it, you'd have to set the password then forget to reboot for it to be a problem.
Basically this whole story is a non-issue. The moderation on the grandparent is a reflection of his failure to reason through this.
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How much do you want to bet that "unnamed customers" are synonymous with "various federal and state police agencies, DOD, and NSA"?
From TFA, those "unnamed customers" are companies that have the need to remotely reboot their machines. This feature is NOT a backdoor - it merely allows someone WHO ALREADY HAS WRITE ACCESS TO THE ENCRYPED DRIVE (i.e. someone who has already given the passphrase) to grant a one-time certificate that permits a reboot without asking for the passphrase again. The major risk here is that someone will rob your store during the 60 seconds it takes to reboot over the phone, a possible, but highly unlikely scenario.