[comp.sys.ibm.pc.misc] Looking for Utility to Zero Out End of Sector

chanel@mensa.usc.edu (chanel summers) (04/26/91)

Can someone point me to a program which overwrites the garbage which fills out
the last sector of a file?  We regularly use Norton's Wipedisk (erased space
selection) for security reasons, but find that sensitive data is, in part
accessible by examining the last sector of a file which has overwritten
a previously-deleted file which HASN'T yet been wiped.

Is there such a program which will zero out the space in a sector after the
end of a file (per its length in its directory entry)?

Reply to this group or by e-mail.  If by e-mail, I will summarize for net.

Chanel

a_rubin@dsg4.dse.beckman.com (04/26/91)

You want to zero out to the end of CLUSTER; I'm pretty sure WIPEDISK doesn't
touch unused sectors in a cluster either.
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My opinions are my own, and do not represent those of my employer.

mussar@bcars53.uucp (G. Mussar) (04/26/91)

In article <32285@usc> chanel@mensa.usc.edu (chanel summers) writes:
>Can someone point me to a program which overwrites the garbage which fills out
>the last sector of a file?  We regularly use Norton's Wipedisk (erased space
>selection) for security reasons, but find that sensitive data is, in part
>accessible by examining the last sector of a file which has overwritten
>a previously-deleted file which HASN'T yet been wiped.
>
>Is there such a program which will zero out the space in a sector after the
>end of a file (per its length in its directory entry)?


There was a similar discussion on BIX a while ago which resulted in 
Jay Vanderbilt writing the COVERUP program.

BIX>coverup1.zip    17408  Approx time: 0:02 at 2400 baud, 0:04 at 1200 baud
BIX>Contributed by: j_vanderbilt  Date: Sat Jul 21 23:51:29 1990
BIX>Ver 1.01 Bug fix.  Erases all but disk structure and data in files.
BIX>This is 99% useless, but when you need it, you do need it.  For when you
BIX>want to be really sure there is nothing extra on a disk.  Overwrites all
BIX>free clusters, the unused space betweeen the end of a file and the end
BIX>of a cluster, and all erased filenames in the directories.  Reports the
BIX>number of bytes in bad sectors found.  Primarily for floppies.  Will also
BIX>work on hard disks, but gives dire warnings first.  Checks the disk
BIX>extensively before running and exits at any sign of trouble.  Should handle
BIX>any standard hard or floppy disk.  Bug fix removes incompatibility with SHARE.

I will attempt to upload this to simtel20.
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