Your code is very confusing, you should not name a namespace sub, and you should give your variables more meaningfull names than @Data!

I also suspect that it is possible to pass you in filenames for the images such as ..\..\..\..\..\..\..\autoexec.bat\0 to overwrite your autoexec.bat file - you should use taint mode on your CGI scripts! Also, you should give out your own names (like 000000.jpg) instead of trusting on anything that a user supplies.

From what I understood of the code, you open the files (via $fHandle->upload()), but you never close either $Data[11] or $Data[12]. Try closing them and the temporary files should be deleted automatically.

I tried to rewrite your code a bit to make it clearer to me, but I couldn't test it:

my $mode = $Data[3];
my $user = $Data[2];
my $imagename = $Data[10];
if ($mode eq "recieve") {
   my ($name_fullsize,$name_thumb) = ($Label[11],$Label[12]);
   my $fh_fullsize = $fHandle->upload($name_fullsize);
   my $fh_thumb = $fHandle->upload($name_thumb);
   if ($fh_fullsize =~ /\.jpg$/i) {
      open (FULLSIZE, ">".$Root."/records/classifieds/fullsize/$user/$
+imagename.jpg");
      binmode(FULLSIZE);
      while (read($fh_fullsize, $fBuffer, 1024)) {print FULLSIZE $fBuf
+fer}
      close (FULLSIZE);
      close $fh_fullsize;
      if ($fh_thumb =~ /\.jpg$/i) {
         open (THUMBNAIL, ">".$Root."/records/classifieds/thumbnail/$u
+ser/$imagename.jpg");
         binmode(THUMBNAIL);
         while (read($fh_thumb, $fBuffer, 1024)) {print THUMBNAIL $fBu
+ffer}
         close (THUMBNAIL);
  } else {      copy($Root."/records/classifieds/fullsize/$user/$image
+name.jpg", $Root."/records/classifieds/thumbnail/$user/$imagename.jpg
+");
      }
   # $Data[11] = $Data[12] = "";
   @Data = sub::clearcarry(0,@Data);
   @Data = sub::pushcommand("preview",@Data);
   goto AllDone;
   }
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perl -MHTTP::Daemon -MHTTP::Response -MLWP::Simple -e ' ;    # The  
$d = new HTTP::Daemon and fork and getprint $d->url and exit;#spider
($c = $d->accept())->get_request(); $c->send_response( new   #in the
HTTP::Response(200,$_,$_,qq(Just another Perl hacker\n))); ' #  web
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