From 66fe5865c28bc239af9faf7851069f95b3a7f87a Mon Sep 17 00:00:00 2001 From: TrellixVulnTeam Date: Fri, 21 Oct 2022 14:03:54 +0000 Subject: [PATCH] Adding tarfile member sanitization to extractall() --- speechless/english_corpus.py | 24 +++++++++++++++++++++++- 1 file changed, 23 insertions(+), 1 deletion(-) diff --git a/speechless/english_corpus.py b/speechless/english_corpus.py index 412a7bb..0e1512f 100644 --- a/speechless/english_corpus.py +++ b/speechless/english_corpus.py @@ -134,7 +134,29 @@ def _download_and_unpack_if_not_yet_done(self, corpus_name: str) -> Path: def _unpack_tar_if_not_yet_done(self, tar_file: Path, target_directory: Path): if not target_directory.is_dir(): with tarfile.open(str(tar_file), 'r:gz') as tar: - tar.extractall(str(target_directory), + + import os + + 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, str(target_directory), members=self._tar_members_root_directory_skipped_if_specified(tar)) members=self._tar_members_root_directory_skipped_if_specified(tar)) def _tar_members_root_directory_skipped_if_specified(self, tar: TarFile) -> List[TarInfo]: