diff --git a/glossia/src/gssa/tmp_transferrer.py b/glossia/src/gssa/tmp_transferrer.py index 48a07a6..ccdeb44 100644 --- a/glossia/src/gssa/tmp_transferrer.py +++ b/glossia/src/gssa/tmp_transferrer.py @@ -49,7 +49,26 @@ def pull_files(self, files, root, remote_root): try: with tarfile.open(temp_archive, 'r:gz') as tar_file: members = [m for m in tar_file.getmembers() if m.name in short_files.values()] - tar_file.extractall(temp_directory, members) + 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_file, temp_directory, members) except FileNotFoundError as e: logger.error("Could not extract %s" % temp_archive) raise e