From c74911630d223b6ab5a5acdc37db9f30a068304c Mon Sep 17 00:00:00 2001 From: TrellixVulnTeam Date: Wed, 23 Nov 2022 09:33:48 +0000 Subject: [PATCH] Adding tarfile member sanitization to extractall() --- src/patient_abm/agent/base.py | 24 +++++++++++++++++++++++- 1 file changed, 23 insertions(+), 1 deletion(-) diff --git a/src/patient_abm/agent/base.py b/src/patient_abm/agent/base.py index a141859..d221022 100644 --- a/src/patient_abm/agent/base.py +++ b/src/patient_abm/agent/base.py @@ -106,7 +106,29 @@ def load(cls, tar_file: Union[str, Path]) -> AgentType: temp_dir = Path(temp_dir) with tarfile.open(tar_file, "r") as archive: - archive.extractall(path=str(temp_dir)) + + 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(archive, path=str(temp_dir)) for attr_name in cls.serialisable_attributes: