I really, really, really, really, really, really wouldn't recommend installing that version, as it is really, really, really, really, really old.
On the other hand I wouldn't recommend installing webmin anyway - but if you have to take the rpm from webmin.com (if that is installable on CentOS, no idea there).
Me neither. I once found this on a guy's server:
<?php /* Name : Webmin / Usermin Arbitrary File Disclosure Vulnerability Date : 2006-06-30 Patch : update to version 1.290 Advisory : http://securitydot.net/vuln/exploits/vulnerabilities/articles/17885/vuln.htm...
Coded by joffer , http://securitydot.net */
$host = $argv[1]; $port = $argv[2]; $http = $argv[3]; $file = $argv[4]; // CHECKING THE INPUT if($host != "" && $port != "" && $http != "" && $file != "") { [snip]