?
Solved

How to make the data untainted in Perl after detecting it is tainted?

Posted on 2004-04-02
5
Medium Priority
?
165 Views
Last Modified: 2013-12-25
I use the -T option in Perl to detect the data is tainted.I then use a regex to verify that it contains only alphanumeric data.Then how do I make it safe if it is tainted??
0
Comment
Question by:Padmaja_vol
[X]
Welcome to Experts Exchange

Add your voice to the tech community where 5M+ people just like you are talking about what matters.

  • Help others & share knowledge
  • Earn cash & points
  • Learn & ask questions
  • 2
5 Comments
 
LVL 17

Accepted Solution

by:
dorward earned 252 total points
ID: 10740038
perldoc perlsec

           if ($data =~ /^([-\@\w.]+)$/) {
               $data = $1;                     # $data now untainted
           } else {
               die "Bad data in '$data'";      # log this somewhere
           }
0
 
LVL 17

Expert Comment

by:dorward
ID: 10740042
(with your own regex obviously)
0
 
LVL 6

Assisted Solution

by:James Looney
James Looney earned 248 total points
ID: 10810852
sub cl { #untaints for safe open/system calls
    $ENV{'PATH'} = '';
    my $path = shift(@_);
    $path =~ s/[\^\~\\;<>\*\|`&\$!#\(\)\[\]\{\}'"\s]//g; #remove metas
    $path =~ s/\.+/./g; #remove ../ exploit
    return $path;
}
0

Featured Post

New feature and membership benefit!

New feature! Upgrade and increase expert visibility of your issues with Priority Questions.

Question has a verified solution.

If you are experiencing a similar issue, please ask a related question

If you get a (Blue Screen of Death), your system writes a small file called a minidump. Your first step is to make certain your computer is setup to record memory dumps. Right click My Computer, choose properties. Click on the advanced tab, an…
This article will show, step by step, how to integrate R code into a R Sweave document
The viewer will learn the basics of jQuery, including how to invoke it on a web page. Reference your jQuery libraries: (CODE) Include your new external js/jQuery file: (CODE) Write your first lines of code to setup your site for jQuery.: (CODE)
In this fifth video of the Xpdf series, we discuss and demonstrate the PDFdetach utility, which is able to list and, more importantly, extract attachments that are embedded in PDF files. It does this via a command line interface, making it suitable …
Suggested Courses

752 members asked questions and received personalized solutions in the past 7 days.

Join the community of 500,000 technology professionals and ask your questions.

Join & Ask a Question