Fwd: Kazaa file corruption

["Russell S/nillion42" <nillion42 () wyoming com>]

--- the forwarded message follows ---
> --- Begin Message ---
>
>
> From: Dave Ahmad <da () securityfocus com>
>
> Date: Tue, 4 Mar 2003 10:21:26 -0700 (MST)
>
>
> Hi Bill,
>
> Could you post this to the vuln-dev mailing list?  The address is
> vuln-dev () securityfocus com.
>
> David Mirza Ahmad
> Symantec
>
> "sabbe dhamma anatta"
>
> 0x26005712
> 8D 9A B1 33 82 3D B3 D0 40 EB  AB F0 1E 67 C6 1A 26 00 57 12
>
> On 4 Mar 2003, Bill Hendron wrote:
>
> > Problem:
> > Lack of file checksum in kazaa leads to the ability to
> > spread corrupted files and corrupt the dowload of any file.
> >
> > Method:
> > By deleting(replacing with hex 00) the data from a mp3
> > file and leaving the headers you can create a file
> > which has identical filesize (kazaa checks filesize).
> > When a kazaa user downloads a file, multiple download
> > streams can be used, if a stream is created to the
> > corrupted file, it will make the download useless once
> > finished not readily appraent until download is complete.
> >
> > Additional:
> > On modems and other areas where compression is used,
> > this can lead to the file traveling at rapid speeds
> > (greater than 20kps on a 56k modem). This could cause
> > the files that are corrupted file or corrupted portions
> > to spread rapdily to other users before the user has a
> > chance to check the quality of the file and delete it.
> >
> >
> > -Bill Hendron
>
>
> --- End Message ---