Fundamentally, my question is "Why is the output of abs_path tainted?" That is, what are the security risks of trusting the output of abs_path, provided that the input data (the relative path) is untainted?

I'm asking because I call abs_path from the inside of a module (VCI) that I maintain on CPAN. I allow callers to specify a relative path to their repositories, and convert that to an absolute path before passing it to Git, CVS, or Subversion (none of which natively support relative paths).

I'm working on making VCI taint-safe.

Provided that the code I'm using to interact with these VCSes is otherwise safe, what risks would I be exposing my users to if I blindly detainted the output of abs_path inside of VCI?

"Don't allow relative paths" isn't an option, because the test suite needs to use them. Also, it would be a definite inconvenience in general.

-Max


In reply to Security risks of Cwd::abs_path (Why is abs_path tainted?) by mkanat

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