Of course there will always be a problem for every solution! Some DOS virii have been known to disable antivirus software in various ways.

The point of the open source code is that by personally modifying it slightly you require a virus to cope with the modification successfully in order to defeat it. This is a problem with a module per se - they are a stationary target! By making it easy for the good hacker to move the goal posts it becomes very difficult for a bad hacker to kick goals.

I was going to post some code that automatically appends a polymorphic form of the original code to every script in your current working directory but as this demonstated both viral design, and worse still polymorphic viral design thought better of it. If you give it a little thought it is easy to write a piece of code that performs a ?have I changed? routine that is never the same and thus hard to defeat.

Why would someone writing a virus to infect your code necessarily care if it breaks your code?

When it comes to virii the analogy to human disease is strong. EBOLA is a very rapidly fatal and highly contagious virus. HIV is a very slowly fatal and not particulary contagious virus. Yet although EBOLA is more contagious the fact that it quickly kills its victims means they have little chance to spread it. So to with a computer virus. If it breaks the program it infects so that it can not run the virus has shot itself in the head as it can not spread as a result of infecting the executable. As such it is not really a virus at all, just a piece of malicious junk.

Ultimately I am less than convinced that we are not discussing the solution to a problem which does not really exist.

cheers

tachyon