In running WordPress, I recommended that my friend constantly update the software, and when he couldn't, make sure to hard-code the fixes. I further recommended disabling as many services and plug-ins as he could.
I strongly suggested that he disable the option to upload files because if someone gets access to that, then he could easily upload a reverse PHP shell or similar tool.
My last recommendation makes the least practical sense: Use the Web server to password protect the WordPress admin directory -- .htaccess file under Apache -- because many vulnerabilities target that very functionality in the application. And, indeed, entering two passwords to gain access is far from functional under normal circumstances.
My friend never had the time to keep completely up-to-date with all the vulnerabilities. But because most of the more serious WordPress vulnerabilities attack the admin interface, the password protection from the Web server saved the day. He describes his experience, other similar solutions and the thoughts behind the risk analysis he performed in his blog here.
While it is always advisable to keep your WordPress blog software up-to-date, using a system that is much more difficult to attack, such as Apache or IIS, raises the bar securitywise. That made my friend's blog less vulnerable to the massive exploitation attacks that try to compromise as many servers as possible.
Then again, if someone targeted my friend specifically, then he may have overcome this hurdle or bypass it completely.
Security by obscurity can indeed be useful as long as it is backed by actual security measures, and as long as you know exactly what it is you want it to protect you from. It does nothing more. That is exactly the difference between the low-hanging fruit the mass exploitations seek and the targeted attacker with a single purpose and resources to reach his goal.
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Gadi Evron is an independent security strategist based in Israel. Special to Dark Reading.