That's not a problem if the regex comes from the outside world: 
$ perl -wle ' "any string" =~ m/$ARGV[0]/' "(?{system 'cat /etc/passwd
+'})"
Eval-group not allowed at runtime, use re 'eval' in regex m/(?{system 
+'cat /etc/passwd'})/ at -e line 1.

[download]

The real problem are denial-of-service attacks with endlessly backtracking regexes.

In reply to Re^2: Perl module search engine by moritz
in thread Perl module search engine by jacques

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