diff --git a/00-Tasks/main.py b/00-Tasks/main.py index 8187d48..77b20db 100755 --- a/00-Tasks/main.py +++ b/00-Tasks/main.py @@ -36,7 +36,26 @@ def _unpack_file(archive, dst_dir): if tarfile.is_tarfile(archive): with tarfile.open(archive) as tar: - tar.extractall(tmp_dir) + def is_within_directory(directory, target): + + abs_directory = os.path.abspath(directory) + abs_target = os.path.abspath(target) + + prefix = os.path.commonprefix([abs_directory, abs_target]) + + return prefix == abs_directory + + def safe_extract(tar, path=".", members=None, *, numeric_owner=False): + + for member in tar.getmembers(): + member_path = os.path.join(path, member.name) + if not is_within_directory(path, member_path): + raise Exception("Attempted Path Traversal in Tar File") + + tar.extractall(path, members, numeric_owner=numeric_owner) + + + safe_extract(tar, tmp_dir) elif zipfile.is_zipfile(archive): with zipfile.ZipFile(archive) as zip_archive: zip_archive.extractall(tmp_dir)