well, after a lot of tests of different conditions, there are many permutations that have unearthed themselves that I wasn't aware of. Namely, using the Scalar::Util suggestion from sgifford, it turns out that the filename used was derived from an environment variable, which caused the taint. The fact that it was a symlink owned by root turns out to have been a red herring, and irrelevant to the problem. I can't say I'd have figured this out without having used the tainted() function from the Util package.

Now that all the sleuthing has been done to determine exactly "why" the filename was tainted, I can program around it accordingly. I'm still feeling residual commitment to my statement that perl needs some programmatic way around this sort of thing, but I'm not exactly sure what that would look like... In principle, I like having the protection for basic stuff, but I also want all that rope to hang myself, should I choose to do so. :-|

Dan Heller
http://www.danheller.com

In reply to Re^2: Insecure dependency in open by argv
in thread Insecure dependency in open by argv

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