Hi All,

I might be totally wrong about this issue, but here if goes.
It is a security issue when using shell escapes (in CGI).
I have a program like 

my $cmd="ls";
my $arg1=" file; ls";
my $arg2=" file";
 
system($cmd,$arg1,$arg2);
warn qx/$cmd $arg1 $arg2/;
warn `$cmd $arg1 $arg2`;

[download]
This generates this output
ls: file; ls: No such file or directory
ls: file: No such file or directory
file
file
file
file
 When using the system command, if 'qoutes' the arguments, which is more safe in CGI. But how do I do this in qx or <backtick>? I can use quotemeta, but isn't there a better solution?

What I want to achieve, is to capture the output of a command, which system will not allow.

Any suggestions?
---------------------------
Dr. Mark Ceulemans
Senior Consultant
BMC, Belgium

In reply to system versus qx security by mce

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