A default installation of Enterprise Linux 4 AS was vulnerable to only 3 critical security issues in the whole two years
This is definitely in direct disagreement with what Microsoft has been saying.
Two worms targetingwere found during the two years, but both affected third party PHP applications not shipped in Red Hat Enterprise Linux 4. In addition, an update to PHP released over three months before one of the worms was released protected systems that had installed the third party applications
Just like what other Microsoft Windows users are saying about non-Windows operating systems, more often than not, the vulnerabilities come from third-party products.
Anyway, read the article and find out more facts about how secure Linux is over the others.