The important question is: Against which sort of threats do you want to defend by using taint mode? If you load from a relative path, then someone might load and execute malicious code. It is the responsibility of your script to decide whether it wants to enable that by untainting the library before using it.

In this situation, for someone to replace the module with malicious code would mean they have access to the directory structure of the website and the cgi-bin. If someone want to do some harm with that level of access, they could do it much more easily then interfering with a module. My best guess is that the only people who could create a symlink are the server admins who, again, could do damage in other ways if they were minded to.

So, I am thinking that untainting $Bin isn't much of a practical security risk in this instance.

Is that sensible or am I being overly optimistic?

In reply to Re^2: Using relative paths with taint mode by Bod
in thread Using relative paths with taint mode by Bod

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