Nobody would say that free software is immune from security problems. And some fear that the availability of source makes some sorts of problems easier for crackers to find. But it really is true that open source makes this sort of deliberate back door difficult to get away with. And it is almost inconceivable that a back door would remain undetected for years. Lest we laugh too much at Microsoft's expense, it is worth reflecting on the fact that Linux has vulnerabilities of its own.
Open source is great, but very few people build their systems from source.
Only your trust in the package builder can determine how you feel about that. One might assume that an engineer building packages for a Linux distributor is more strongly motivated to do the right thing than a Microsoft engineer, but that is never guaranteed. Sooner or later, somebody will probably get burned by a bad binary package. It can happen to us too. Update on Corel Word Perfect Office 2000 .