I was discussing security with a co-worker who needs to process user-defined pathnames. We have an app that allows users to upload files for their websites. We will not just open the box to use FTP. That is not an option. ;-)

While beginning to demonstrate an idea of a regex to deal with (pronounced: prohibit) paths like: /etc/passwd and ../../../someFile, common-sense kicked in and persuaded me to look for the pre-invented wheel.

A search through Perl Monks revealed nothing complete, and CPAN seems to have no modules to handle this very common task.

Where can I find pathname validation code?

Russ

In reply to Upload Security (strip ../, etc.) by Russ

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