cadcmcr

Hi, I've been using this computer for a few years now and I'd like to sell it, the only thing is I've literally used 10 or so credit cards in the last few years buying things online and I'm worried that the hard drive is a tech criminals wet dream!?!

I'm wondering, does Killdisk utility fully delete data to the point where it would literally be impossible for any data recovery expert, FBI lab, or even Jesus to recover data?

Does Killdisk delete the g-list sector of the drive? If not what utility will do this?

Can people or the FBI really recover data using magnetic microscopes or whatever?

I have not found a definitive answer on the internet after hours of research regarding the effectiveness of Killdisk or simliar utilities in deleting bad sectors or g-list sectors of the hard drive.

Thanks in advance.

raptor_pa

OK Let's see here questions in order
1) The FBI ( or more likely CIA and NSA ) and Jesus all have a reasonable shot at recovery.after running killdisk. The question becoms diminishing returns. Reselling information your 10 CC #'s on the open market are worth anywhere from $10 - $100 for the group of 10. Unless they are VERY high limit cards. then they may go for $50.00 each. The type of people who would attempt recovery are not going to use the cards, they would resell the information.

Killdisk does not do the g-list. The G-list is in the service area ( SA) of the drive, an area inaccessible to user apps. The apps don't need to know the bad sectors, the disk firmware needs to know in order to remap that logical block to a spare logical block. Special hardware/software is required to read the g-list area and either read those sectors or blank the g-list so the sectors are available. Cheapest product I've found to do it is about $2000. Keep in mind tho, if the sector went bad, it is probably not readable reliably anyway.

There are other technologies besides Magnetic Imaging Microscopes that can be used to recover data from the platter surface. Spin stands can also be used. Again diminishing returns. If someone is taking the extra effort and time to look this deep, then they are looking for a lot more than your credit card numbers, and have a reasonably good idea what they are looking for and that it exists on the drive.

If security is that much of an issue for you, I would suggest rather than spending all the time looking for software, buy a new or refurbed drive to put into the machine you are selling. Open up your old drive, remove the platters, take some good course sandpaper or a grinder to all the platter surfaces, then place all platters into a tapedup stack in cloth bag, run a drill though the platters a couple of thimes, then take a large hammer and reduce the platters to as small pieces as possible. Alternatively soak platters overnight in some good strong acid :)

Now that being said. 0 Wiping IS acceptable for anything other than DOD classified information. the National Association for Information Destruction certification for digital data destruction does not specify methods of wiping, only the result that they must have. properly applied killdisk, dban. and many other wipe tools will pass the testing easily. And is probably more than sufficient for your uses.

cadcmcr

Thanks for the info. I have been doing some reading though and apparently, as long as a utility supports it, there is something called ATA-SE ("SE" standing for SecureErase) that can be wiped with modern utilites like Killdisk. Most ATA drives made after 2001 support SecureErase.

I'm curious, so if I have a supported drive will Killdisk then utilize SecureErase with its normal wiping routine?

BTW, what are the chances that any sensitive information, like credit card numbers or search logs, would actually be on the g-list sector? What is the normal function of the g-list anyway and why would it contain any of this information?

Thanks again.

dai

i think the pro version of killdisk overwrites and deletes about 9 times
the free version you have to do it manually

raptor_pa

The g-list is the 'grown list' of bad sectors. The g-list itself only contains the addresses of blocks or sectors that o bad during operation. These are then mapped and recorded in the drives parameters in the SA area ( translation table) to point to what were 'spare' sectors when the drive left the factory. The g-list itself doesn't contain any data, but the pointers to the sectors that are bypassed. The chances of the bad sectors containing any information are the same as any other sector that has ever been written to. Clearing the g-list means that those sectors will now be readable, or at least one hardware device will read the g-list and hunt down just those sectors for cloning. Bu since they were bad enough at some point to be marked, what are the chances it will be readable now. Secure erase come in two flavors of implementation. Killdisk does not implement secure erase, SE is a low level command, there is a freeware console app out there that will implement it. If I read the documentation on it correctly, the first version of SE does not process p and g list sectors ( The p-list is the permanent list of bad sectors, those that were marked bad at the factory and should never be used) I beleive Enhanced SE does process the g-list.
Secure Erase info and utility from here http://cmrr.ucsd.edu/people/Hughes/SecureErase.shtml
Seriously tho, if your only interest is cleaning this one drive, replace it and physically destroy the one with your data on it. If it's a learning experience then have a blast!!
Also you could run killdisk on the drive, then try some of the recovery tools so you can see what exactly is left. or do a zero wipe and use winhex and do a boolean searcg for hex values that are not 0, that would show you any unwiped sectors.
Have fun!

linderman

there is no user data in the G-list


use Dariks boot n nuke and sleep safely

cadcmcr

lol, raptor pa I'm beginning to think you're trying to sucker me into destroying these drives lol.

Thanks for the advice btw it helped, I guess I'm just being paranoid. Besides most of these credit carts aren't even valid anymore haha.

raptor_pa

LOL, Dban is perfectly acceptable, we use a customized implementation to do certified digital destruction for banks, medical facilities an industry. I test samples every two weeks, and every two months we send samples to another data recovery shop. Never recovered any data from them.