Open source doesn't make software safer
There is this ludicrous paradigm among the technorati that just because a piece of software is developed collaboratively and by enthusiasts with source code shared freely on the web, that automatically makes it more secure and less buggy.
"When everyone can look at your code," runs the argument, "flaws get found more quickly and patches get released almost immediately."
But although everyone can look at open source code, in practice, the only people who do are those involved in developing the software and those trying to create malware that exploits it.
This is exactly the same situation that applies to closed source software, except that it is somewhat harder for the hackers to get their copy of the code.