I would call that a programmer error. The language certainly does make it harder to write "safe" code, but it is certainly doable.
I guess my point is that the tools/libraries/frameworks on top of the language are what make it useful or not useful, independent of the language itself. For example, writing a web app in Ruby may not help you against SQL injection (http://en.wikipedia.org/wiki/SQL_injection) unless you have a well designed query language on top of that.