Home page logo

basics logo Security Basics mailing list archives

RE: Suggestions on free XP hard drive wiping utilities?
From: "Phillips, Mike" <PhillipsMike () otc army mil>
Date: Wed, 12 Feb 2003 13:04:46 -0600

I work as a contractor for a government agency & can confirm that this is
correct. There are (not free) tools that we use to wipe hard drives for
re-use in the same classified environment, but we do not allow disks that
are classified to ever be used in an unclassified environment. When the
disks are no longer usable, they are physically destroyed. I've been told
that we have some tools that can supposedly recover data from hard drives no
matter how "wiped" they are, but I have no personal experience with them.

Mike Phillips

-----Original Message-----
From: David Verty [mailto:verticalrave () hotmail com]
Sent: Tuesday, February 11, 2003 9:11 PM
To: security-basics () securityfocus com
Subject: RE: Suggestions on free XP hard drive wiping utilities?

There is a whole thread on ExtremeTech about this I believe...and it 
stretches on for a long run. You might find some useful information there, 
like DoD (Department of Defense) standards, and software that exceeds it for

deletation of files.

What the government does right now to permanently get rid of data is shred 
the disk in a metal shredder.

Are there any programs for secure deletation? Never heard of any really that

were extremely good.

And i've heard of hard disks storing everything in so called 'layers' (you 
have to rewrite your disk three or four times+ with phony data to truly get 
rid of everything.) but the edge thing is something i've never heard about. 
Interesting. Somebody on ExtremeTech also mentioned that since the signals 
are theoretically magnetic, its possible to extract the strength of the 
previous magnetic signal (though weak) and rebuild the data from there. 
Whatever validity that has i'm not so sure.

From: "MacFerrin, Ken" <Ken_MacFerrin () csgsystems com>
To: <security-basics () securityfocus com>
Subject: RE: Suggestions on free XP hard drive wiping utilities?
Date: Tue, 11 Feb 2003 11:20:16 -0600

There are dozens of tools that will "clean" your hard drive by overwriting 
your data in various patterns and such and most any of those will give you 
"decent" security, but.. none of those are going to make the data 
irretrievable to someone with the right equipment.

I'm no expert but the basics of being able to retrieve data stem from the 
fact that when the HDD head overwrites the data it's never able to 
perfectly write along the same track that it did when writing the original 
data.  This leaves an "edge" of data that wasn't quite overwritten and that

"edge" is enough for someone with a basic setup (about 1500 USD) of 
specific equipment to go back and pull the original 1's and 0's off the 
disk..  The only way to truly "clean" the disk is using equipment 
specifically designed to drive the head at a higher voltage to create a 
wider write track and re-write random patterns many times.  From what I 
understand though even these re-writes will leave some residue that could 
be picked up by some high-end gear and a skilled operator.

Essentially, if the data was really that sensitive, you need to physically 
destroy the disk..

-----Original Message-----
From: Joris De Donder [mailto:joris () digitaldefense be]
Sent: Tuesday, February 11, 2003 6:21 AM
To: 'security-basics () securityfocus com'
Cc: Champion, Steve
Subject: Suggestions on free XP hard drive wiping utilities?

Would someone please throw out a URL and suggestions for free Windows 
hard drive wiping utility's?


  "Eraser is a secure data removal tool, which allows you to remove
   sensitive data from your hard drive by overwriting it with carefully
   selected patterns.

   The program is free software, which means that everyone has
   access to the source code,..."

Joris De Donder

MSN 8 with e-mail virus protection service: 2 months FREE*  

  By Date           By Thread  

Current thread:
[ Nmap | Sec Tools | Mailing Lists | Site News | About/Contact | Advertising | Privacy ]