It is a common notification that open source as opposed to the proprietary software is more prone to breaking down due to the ability of code crackers to manipulate the source code to malfunction. While this point of view is justified, because you can actually see the code, modify it and re-distribute it, it would be very presumptuous to say that it is unstable and unsecure. With the advent of internet businesses that operate completely online, security became an inevitable need and an unavoidable concern. This also does not mean that proprietary software is uncrackable (given the fact that there is no access to source code and there is a huge price via licensing) the most standardized software can be invaded due to their predictability as well. And the debate never ends!
There are so many misconceptions about the open source development, that it is very difficult to create a leased platform for a debate. Along with misconceptions, there are not as many skilled professionals to clear the cards too! Someone to take a stand and “show” the architecture of the open source code to the masses at large and prove some point! Well, that's true even with a closed source code as well – due to the non disclosure of code policy no one can vouch that proprietary software is “highly secure” – other than the developers themselves!
Firstly, just because the source code is available, does not make open source software inherently more vulnerable. This would pretend that there are absolutely no vulnerabilities in proprietary software – which is totally untrue! Standard software can be manipulated too via scripts because of their predictability of functionality. In fact, the availability of source code to a developer enables new avenues for a developer to secure it in a customizable way as per requirement per project basis. Web development – one of the ever expanding fields in IT, also has caught on the open source train. With loads of open source development platforms like PHP, Drupal, Joomla etc, building web applications using these is a trend that has been addressed on rapidly in the past few years. Of course this did not lessen the charm of the standard software and ASP.NET and ASP are used equally as well. However, to put it in plain language, there are no statistics that show one to be more vulnerable than the other.
So, with open source development, or with proprietary software, your website / application is equally vulnerable (or not) and can be taken advantage of by a notorious hacker. Like the saying goes “A lock on the door is for a gentleman, thieves will steal anyways”. Whether you use open source development or not, you must appropriately secure our applications and websites and leave very less scope for manipulation by code breakers and hackers. With all said and done, use the apt software to suit your development requirements and ensure that your final product is free from vulnerabilities while thoroughly tested by all testing strategies available and secured to your satisfaction.