Re: perl-cgi hole in UltimateBB by Infopop Corp.

From: Brock Sides (bsidesat_private)
Date: Fri Feb 18 2000 - 07:45:48 PST

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    On Thu, 17 Feb 2000, I wrote:
    
    > Perl's tainting mechanism only comes into play if you are invoking a
    > external command in some way: via system, exec, backticks, or opening a
    > filehandle to or from a pipe. For example,
    
    I need to correct myself here, before Randall does it for me. :)
    
    Perl's tainting mechanism will also come into play when opening a
    filehandle for writing:
    
    [bsides@koala /tmp]$ cat splort.pl
    #!/usr/bin/perl -T
    $ENV{PATH}=''; # we need a safe path
    $ENV{BASH_ENV}=''; # and a safe bash env
    open(PW, ">$ARGV[0]") or die $!;
    print PW "splort\nsplort\nsplort\n";
    __END__
    [bsides@koala /tmp]$ ./splort.pl splort
    Insecure dependency in open while running with -T switch at ./splort.pl
    line 4.
    
    --
    Brock Sides
    Unix Systems Administration
    Towery Publishing
    bsidesat_private
    



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