I am new to LimeSurvey. And this is my first encounter with the software.

First I have to admit that your job is very helpful to our college and community.

I am concerned about the security of the application and the possible attacks or backdoors that by installing this application on my server, it can cause for me. How can I be sure about the security of the software? What can I do to increase the security, as an admin?

Thank you for your help and I am only asking this because I found these on the net:

www.exploit-db.com/exploits/19330/
www.exploit-db.com/exploits/18508/
www.exploit-db.com/exploits/4544/
www.exploit-db.com/exploits/4156/

Thank you
And please keep up the good job.

That's a good question. Limesurvey is a lot like any "user generated content" application and users can try to exploit that. And because it's open source anyone can look under the hood and look for exploits

But then, anyone can also report problems to the developers also. I know they respond quickly to this stuff. Here's an example from the bugs site. Look around and you'll see others.
bugs.limesurvey.org/view.php?id=7105

There are some installation security hints in the manual. Most of this is typical Linux application security: docs.limesurvey.org/Installation+security+hints

BTW, most of those exploits you posted are ancient.

Two of these issues are from 2007 so they are more than 5 years old. Another one refers to the old 1.91 version which isn't used that much and the latest issue is already fixed as well.

Anyway, if you find any further issues, please file a ticket at our bugtracker and we will fix it as soon as possible.

I know. And thanks for calling them ancient not anything else...
I just wanted to have a ruler to measure how sure I can be with my lovely LimeSurvey installation, that's all.

If an exploit is discovered for pre 2.0 ..eg 1.92+ 120919 will there be any patches?

No, sorry.

On a similar note, what happens when I delete any survey post completion, does it deletes just the tables or everything from my server or Lime Survey's server? Is there any possibility that someone can sneak in later and get an access to the deleted surveys?(Survey script, Datafile, Tokens along with contact list)