Bug 2218875

Hello,
In RHEL 9.3 and 8.9, we're planning to fix the long-standing CVE-2007-4559: Python's `tarfile` module makes it too easy to extract tarballs in an unsafe way.
Unfortunately, for the CVE to be considered fixed, this needs a behavior change. (If you don't think this is the case, let's bring it up with the security team.)
Upstream, Python will emit deprecation warnings for 2 releases, but in RHEL we change the behavior now, emit warnings, and provide ways for customers to restore earlier behavior.
To avoid the warning, software shipped by Red Hat will need a change.

For more details see upstream PEP 706: https://peps.python.org/pep-0706
and the Red Hat knowledge base draft: https://access.redhat.com/articles/7004769

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In /usr/share/anaconda/addons/org_fedora_oscap/common.py, oscap-anaconda-addon calls `tfile.extractall()`. The call will emit a warning by default. To prevent that, add something like this before the call:

tfile.extraction_filter = getattr(tarfile, 'data_filter',
                                  (lambda member, path: member))

This is compatible with unpatched versions of Python. If you only build for RHEL8.9+, instead add an argument to the call:
`tfile.extractall(path=out_dir, filter='data')`.

The 'data' filter above attempts a "safe" extraction, intended for pure data archives. For example:
- prevents extracting outside the target directory, and to absolute paths (by raising an exception)
- prevents symlinks pointing outside the target directory, and to absolute paths
- adjusts permissions (for the owner, only the executable bit is honored)
See PEP 706 for details: https://peps.python.org/pep-0706/#filters

If you trust the tarball, use `'fully_trusted_filter'` (or `filter='fully_trusted'`) instead. That will preserve the existing behavior.

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Let me know if you have any questions!