I am sure this is not directly related to Perl, however, I am hoping I can get some wisdom regarding this security problem I am faced with. I do use CGI/Perl for my websites

I have a virtual private server with a web host. I have a few of my websites hosted there. The VPS is just for my own websites and I have not given ssh access to anyone else. I would like to think my passwords are quite secure. But someone was able to put a php file in the document root of one of my websites with both the owner and group being 'nobody' - This could seem like the file was put there via http. I am a novice. I have given below the listing of the file (flight.php). My web host says to look for scripts through which this could have been done. I would appreciate your help and if you can refer to some material that I can read to understand how I can secure my perl scripts. 

-rw-r--r--   1 subhasri subhasri      0 Aug 19 11:44 .htaccess
-rw-r--r--   1 subhasri subhasri 546324 Aug 19 11:45 error.php
-rw-r--r--   1 nobody   nobody     2318 Aug 20 11:00 flight.php

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In reply to Phishing question by Anonymous Monk

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