I'm working on the second lesson of my online CGI course and ran into a bit of a stumper.

I'm demonstrating why most alternatives to CGI.pm fail on file uploads and I use the following script to show the contents of <STDIN> following the browser POST: 

#!c:/perl/bin/perl.exe -wT
use strict;

my $buffer;
read (STDIN, $buffer, $ENV{'CONTENT_LENGTH'});
print "Content-type: text/plain\n\n";
print $buffer;

[download]
Now generally, if the Content-type is test/html, this represents a security hole as some user could enter a dangerous SSI (e.g. <!--#exec cmd="/bin/rm -fr"-->). If the Web server is configured to allow SSI interpretation in CGI scripts, you've just had a bunch of files wiped out with that. However, if the Content-type is text/plain, do the servers ignore SSI? If it is in any way possible for such an SSI to be entered in such a script, I would like to include that in one of my "Security Checkpoints."

Cheers,
Ovid

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In reply to Security question by Ovid

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