[throwawaykf09]

Also, many open source proponents claim that open source software is more secure because the “many eyes” theory will lead to bugs and vulnerabilities being discovered sooner. This and other high profile exploits like heartbleed show how well this theory applies in practice is questionable.

[lillesvin]

I find that conclusion presumptuous. Unless you can say how many bugs would have been discovered had the source been closed, then it doesn't make sense to claim the opposite.

Also, do we know that e.g. this and Heartbleed were discovered by reading the source? If they weren't then the availability of the source code is inconsequential IMO.