I think you misapprehended my point (or I misapprehend yours). Suppose the client request to a Perl script sets the environmental variable BAD_VAR. In Perl, $ENV{BAD_VAR} is tainted. Suppose your CGI script is 
#!/usr/bin/perl -wT

print "Content-type: text/plain\n\n";
local $ENV{PATH} = '/usr/local/bin';
print `my_prog 12345`;

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From my understanding, Perl will not raise any issue in the scenario where my_prog accesses BAD_VAR, and hence %ENV can be used to bypass taint. Is this not correct?

#11929 First ask yourself `How would I do this without a computer?' Then have the computer do it the same way.

In reply to Re^4: Taint and Shellshock by kennethk
in thread Taint and Shellshock by kennethk

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