How safe is Gutmann method?

z3r0aCc3Ss · Post by **z3r0aCc3Ss** » 04 Sep 2009, 11:14

How safe is Gutmann method for entirely deleting your data?
Coz, I have heard that FBI (or some soft of agency, like that) was able to recover data from a damaged HDD, and I mean physically damaged.

So, is it possible to delete all your data with Gutmann? I mean, is it safe?

I used DoD (Short), and it worked, at least for me, in my country, coz, here cyber crimes and crime branch are still in child state. n00b

So, are there any chances to recover the data even after using Gutmann?

I used DoD (Short) and then tried every way 2 recover my previous data, but I couldn't recovered, Im happy

.

Post by **DNR** » 04 Sep 2009, 11:33

I am glad you found this, since I knew you were studying how to wipe a HDD.

An overwrite session consists of a lead-in of four random write patterns, followed by patterns 5-31, executed in a random order, and a lead-out of four more random patterns.

Each of patterns 5-31 was designed with a specific magnetic media encoding scheme in mind, which each pattern targets. The drive is written to for all the passes even though the table below only shows the bit patterns for the passes that are specifically targeted at each encoding scheme. The end result should obscure any data on the drive so that only the most advanced physical scanning (e.g. using a magnetic force microscope) of the drive is likely to be able to recover any data.

Floodie had previously talked about restoring the magnetic field in a sector to recover data. This said what floodie meant well*:

The permittivity of a medium changes with the frequency of the magnetic field. This means that a lower frequency field will penetrate deeper into the magnetic material on the drive than a high frequency one. So a low frequency signal will, in theory still be detectable even after it has been overwritten hundreds of times by a high frequency signal.

The patterns used (in the Gutmann method) are designed to apply alternating magnetic fields of various frequencies and various phases to the drive surface and thereby approximate degaussing the material below the surface of the drive

*I'll let floodie weigh in if I misspoke, but this is what I understood from his words.

I guess it depends what level security you want when you wipe your files.
You could be satisfied with the write/overwrite/write again of most wiping programs, but the Gutmann method is another layer of security you can use for higher level data. Overkill?

The debate continues on recovering deleted files:

However, once the space is overwritten with other data, there is no known way to recover it. It cannot be done with software alone since the storage device only returns its current contents via its normal interface. Gutmann claims that intelligence agencies have sophisticated tools, among these magnetic force microscopes, that, together with image analysis, can detect the previous values of bits on the affected area of the media

DNR

Lyecdevf · Post by **Lyecdevf** » 04 Sep 2009, 14:02

One day I am just going to take a nice little boat ride across the sea and dump the hardrives into the sea. I am sure that is going to work better than any thing else.

Pong18 · Post by **Pong18** » 04 Sep 2009, 20:05

yeah me too i was thinking of the boat ride also some time ago and i was thinking also of air dropping it... i was thinking on going on boat ride and just throw my hard drives in the center of the mariana trench in the pacific after chainsawing it in half, i was thinking of air dropping or sticking to a tomahawk my drives from the sky's ceiling to the concrete surface of flat land... hehehe this was my fantasy when thinking of ways to destroy data with some taste of humor... hahaha! the sky is about 101,706 feet and the mariana trench about 35,798 feet. so planting my drives to an imploding kind of missile from the ceiling to the trench floor is about a hundred and thirty six thousand feet! imagine the damage it would make of the disks. hahaha! LOL!

Post by **DNR** » 04 Sep 2009, 21:07

I would take the HDDs and put them in a steel bucket. Add iron oxide(80%) and aluminum powder(30%), drop a road flare in the mix and run(or add gunpower smokeless or black- to get the fire going).

DNR

Post by **Gogeta70** » 04 Sep 2009, 21:43

AKA, Thermite, DNR.

Pretty effective. That's how i would destroy my data: melt the shit.

Lyecdevf · Post by **Lyecdevf** » 04 Sep 2009, 22:34

[quote="DNR"]Add iron oxide(80%) and aluminum powder(30%)[quote]

....

80% +30%=110%

z3r0aCc3Ss · Post by **z3r0aCc3Ss** » 04 Sep 2009, 22:40

Well, I tried to delete my data.

My config is:
Intel Core2Duo 2.2 GHz E4500
2 GB DDR RAM
160 GB HDD, (Now it's 152 GB, after wiping)

I used DoD Short method.
PRNG = Mersenne Twister (mt19937 ar-cok)
Rounds = 1
Passes = 3
Runtime = Approx. 4 Hrs
Throughput = 40,000 KB/S - 90,000 KB/S

Well, I tried Gutmann before DoD Short, and it was showing me 68-72 hrs just for 160 GB HDD and that too for only 1 round with 35 passes.
So, thats approx 3 days and I can't spare 3 days just to delete my data securely. Instead, I will buy a new HDD. So, I tried DoD method and its good for me.
I used many softwares to recover my data, but I couldn't recover, so, thats fine wid me and in my country also, as small-medium cyber crimes take place on regular basis and no one has time to check all these things, as they dunno all abt this, cyber crime branch is still noob and corrupted.

Anybody tried successfully Gutmann?

f4Gg0t_43 · Post by **f4Gg0t_43** » 05 Sep 2009, 00:28

z3r0aCc3Ss wrote:Anybody tried successfully Gutmann?

I use Gutmann every time I empty my recycle bin. I'm not sure how good it is though. It usually takes like ... 15 minutes per 1gb.

z3r0aCc3Ss · Post by **z3r0aCc3Ss** » 05 Sep 2009, 02:44

f4Gg0t_43 wrote:
z3r0aCc3Ss wrote:Anybody tried successfully Gutmann?
I use Gutmann every time I empty my recycle bin. I'm not sure how good it is though. It usually takes like ... 15 minutes per 1gb.

Can u tell me such a software?
I use dban, but need some different software.
PM me or post here pls.

Post by **bad_brain** » 05 Sep 2009, 04:48

try the "Ultimate Boot CD", there are 5 disk wiping tools on it (DBAN too):
http://www.ultimatebootcd.com/

Lyecdevf · Post by **Lyecdevf** » 05 Sep 2009, 05:55

z3r0aCc3Ss wrote:Anybody tried successfully Gutmann?

I did! I wrote about it in my blog so I am not going to tire you here. I am just going to say that I had this impression that I was, "tickling" the hardrive.

z3r0aCc3Ss · Post by **z3r0aCc3Ss** » 05 Sep 2009, 05:55

bad_brain wrote:try the "Ultimate Boot CD", there are 5 disk wiping tools on it (DBAN too):
http://www.ultimatebootcd.com/

Thanks b_b, will try soon.

f4Gg0t_43 · Post by **f4Gg0t_43** » 05 Sep 2009, 11:10

z3r0aCc3Ss wrote:
f4Gg0t_43 wrote:
z3r0aCc3Ss wrote:Anybody tried successfully Gutmann?
I use Gutmann every time I empty my recycle bin. I'm not sure how good it is though. It usually takes like ... 15 minutes per 1gb.
Can u tell me such a software?
I use dban, but need some different software.
PM me or post here pls.

CCleaner

Post by **DNR** » 05 Sep 2009, 12:15

well again Gutmann might be overkill for each time you empty your wastebin. But I suppose it depends on what you are downloading

80/30= Thermite is 8 grams of iron oxide to 3 grams of aluminum.

DNR