I’ve always seen these in movies or tv shows. The cops bust into a guys apartment and he is some kind of super computer hacker. Before they can get to him, he pops a floppy in the computer, and boom! It’s all whiped clean of the evidence the cops were looking for. So, I gotta ask, can this really be done?
Not really, if the cops are on the ball; all they have to do is unplug the thing. Any kind of serious data wiping takes time, depending on how large the hard drive is. If you just start the process when the police burst in, it’s just not going to happen.
This where having some thermite placed on top of the HD with a magnesium fuse ready to go comes in really handy.
Heh. Even faster: wrap your drive with several turns of det cord with an electrically-ignited cap. One press of a button will turn your HD into confetti instantly.
I don’t see the problem with building a powerful electromagnet that surrounds the entire HD enclosure. It would never have been used before so it wouldn’t screw with the drive during normal operation. One button and it wrecks the whole thing in a few seconds.
It would be a very small and quick program to overwrite data that is critical to the easy access to significant data on a hard drive: the partition table and the boot sectors.
The resulting disk would, at first glance, appear to be blank or not readable. But to a computer expert, if no one else messed with it first, it could be easily restored.
Yeah, short of explosives or high-powered electromagnets, it’s not gonna happen. Simply wiping the FATs on your hard drive(s) only eliminates the pointers to the actual data. The data is still there. Data shredders take a great deal of time to do the work, since they have to go over every bit of data on the hard drive and either scramble it or write zeros to it. Depending on the size of your hard drive and the method employed, that could take hours.
Now, if you stored all of your data on an SSD then the process might be faster, but it would still take time.
Nope, I wouldn’t count on it. Remember that right inside the drive are two of the most powerful ceramic magnets you’ll encounter in everyday use just an inch or so from the platters. Besides, most drive enclosures are made of steel, which pretty effectively shields them from external fields anyway. I’ve run them through the center of a CRT degaussing coil with no effect on the data whatsoever. You might be able to erase some of the data with a powerful enough magnet, but you’re most likely going to leave some traces which can be recovered. The best you can hope for is to wipe out some of the servo data along with the actual drive contents, but the police would only need to bring the drive to the manufacturer to have the servo tracks rebuilt. Remember, you’re up against state resources; nothing but total data destruction will do. And you’ve only got one shot at it, so you better use a method with 100% guaranteed results.
In concept, that works. In practice, it might require a much bigger magnet than you might imagine, or a special installation of magnets mounted directly on the disk enclosure if your design is to remove all traces of data (compared with just causing random disruptions).
I don’t know how much of a magnetic field would affect a 2007 PC hard drive, but I know that my monster demagnetizer for mag tape has a hard time with the newer tape media. It was designed for 1/4" audio mag tape (1/2" if you turn the cart or reel over) and it worked great for that material. But I have to wipe DV (video) carts (thinner than 1/4" audio tape) across the base several times in different directions and for several seconds before the data is made into total junk.
So the mag field would have to penetrate quite a bit into a metal drive enclosure and be of sufficient strength to do the job. Might be difficult.
I wonder if anybody’s ever manufactured a drive with either a physical or magnetic self-destruct mechanism. If built into the drive, it shouldn’t be too hard to do. I’m imagining the HDD having a couple extra pins, apart from the usual connector, and a manufacturer’s warning along the lines of “12 V DC applied to these pins will make the disk destroy/erase itself”. The user can then rig up a self-destruct button if desired. Apart from the limited audience who would find such a feature a useful safeguard, you would have thousands of geeks who thought it was cool, at least until their cat sat on the self-destruct button.
I’m unaware of a fast (software based) way to irretrievably erase a HD. A far more effective method would be to be using an encrypted disk. An unmount operation followed by rebooting would be fairly quick.
May be thorough, but it’s not fast. Check their FAQ.
And for something that I think might work would be for the drive to spin up to full speed and then drop and scrape something along the platters to scratch them up, maybe along with sending the heads all over rewritting garbage info.
As for the magnet theory. I bought an MRI machine. I keep all secret info on an external drive in the center of the machine. For added effect, the computer and half the stuff in the room should slam into the machine as well when I power it up.
The EP-3E Aries II spyplane comes with a self destruct mechanism installed. Unfortunately the links all seem to be full of varying degrees of bullshit as to what all’s involved (Amitol???). Not too surprisingly, a search for “Anticompromise Emergency Destruct” (ACED) turns up very little public information.
I’ve seen ATX PSUs with built-in uninterruptable power supply - they only provided about ten minutes of backup power due to the small size of the batteries, but that would probably be enough to trash a fair bit of data - keep all the critical stuff in its own partition and the task becomes a bit more manageable.
Based on investigations I’ve been involved with, the cops DO NOT have unlimited forensics budgets. I’ve seen the cops choose to go without some evidence because the cost associated with doing a good job of pulling data they wanted would interfere with their ability to prosecute other investigations.
Now if our OP is Osama bin Laden’s office manager, yeah, the government would force the gates of hell to get every byte on the drive, but I’ve even seen agencies at the statewide level that simply walk away from doing recovery on a drive that’s failed.
This is true, of course, and I did not mean to imply that they did. However, if you feel the need to go to these extraordinary lengths to destroy your data at a moment’s notice, it stands to reason that it is important enough for law enforcement to exhaust all reasonable means to extract it. Otherwise, you’re just being overly paranoid. 
The only practical way of “instantly” erasing the disk that I can think of is to raise the temperature of the platter’s surface above its Curie temperature. Assuming a single surface, single platter, disk drive, the metal cover could be replaced with a transparent substitute. Then you would need an external radiation source with enough intensity to quickly heat the platter’s surface to the Curie temperature. Something like a chemical laser.
The problem with thermite is that it may get classified as a destructive device and you might get charged with arson. Then there’s the whole burning your house down thing. I was taught how to use it in the military for the destruction of sensitive equipment. Once ignited, you get out of the building as quickly as you can.
There was a sort of urban legend running around the last year I was at school, that you could somehow coat a floppy disk with the material from the head of a match and destroy someone’s drive with it. It did the rounds along with the grenade made from a match head filled tennis ball, throw it and watch it explode! 