At first, we have to find out what does “of them all” refer to in the title. Did I mean WordPress, Joomla and other open source CMSs, or proprietary CMSs? Well, I meant both. After all, Drupal's Dries Buytaert said in an interview recently that they consider proprietary CMSs as their competitors, not majorly WordPress et al. So, if Drupal is to be judged, it'll be judged of them all, which is certainly a tougher ballgame. Is open source secure or vulnerable? Many people have a big misconception about open source software – since its source code is available, it's vulnerable to a plethora of threats. But over the years it has been proved that open source is as secure as proprietary CMSs, and that all the naysayers were terribly wrong. Open source, in reality, helps you customize the code as per your needs (as whitehouse.gov and many other sites have done) and is a progressive step towards a better web and stronger security. Who all mainly complain about Drupal's security? Users that don't upgrade to the latest version complain about Drupal's security the most. This means users have to be more active regarding how they manage their website or else they are vulnerable, no matter how much bugs Drupal fixes every now and then. Drupal has an open bug-tracker as well to show its users what bugs have been fixed and what are yet to be. What all Drupal does to make sure it's secure? Drupal API is a powerful one – one that has solutions for many threats like injection and cross site request forgeries. Moreover, the company is backed by a dedicated security team and is know for getting updated more frequently than any other CMS. And let's face it: Most attacks to a Drupal site are due to a customized, unscrutinized theme or module in use and not necessarily a pitfall in Drupal core. So, is switching to Drupal a right choice? Drupal powers millions of websites across the world today. Its share in govt. , .edu and media sites in the US surpasses all other CMSs. It is used for powering the largest of sites as well as the small ones. Wrapping up Finally, you can make out from the above analysis that Drupal is a secure CMS and it all finally depends upon how you manage your Drupal site. Other open source CMSs such as WordPress and Joomla also provide good security but if you're looking for a CMS that is almost invincible, zero in on Drupal only.
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