GHSA-wcmj-x466-56mm: OpenTofu: Provider cache installation follows root-module-controlled package directory symlink and writes outside the working tree

If a symlink already exists under the .terraform/providers directory where a provider package needs to be installed, tofu init would follow that symlink and install the new package content into it.

If an attacker can coerce an operator into running tofu init in a directory whose contents are attacker-controlled, they can include such a symlink along with instruction to install an attacker-controlled provider package at the path of that symlink, which would then cause OpenTofu to write the contents of that provider package into an arbitrary directory elsewhere in the filesystem if the OpenTofu process has sufficient permission to write there.