From 4781f49ab9a7171b5a6f8b07c5f003a18ec30fd4 Mon Sep 17 00:00:00 2001 From: TrellixVulnTeam Date: Sat, 22 Oct 2022 18:48:43 +0000 Subject: [PATCH] Adding tarfile member sanitization to extractall() --- batch_pipeline/pipelines/score.py | 24 +++++++++++++++++++++++- build_pipeline/pipelines/evaluate.py | 24 +++++++++++++++++++++++- 2 files changed, 46 insertions(+), 2 deletions(-) diff --git a/batch_pipeline/pipelines/score.py b/batch_pipeline/pipelines/score.py index 178169b..bfa1445 100644 --- a/batch_pipeline/pipelines/score.py +++ b/batch_pipeline/pipelines/score.py @@ -26,7 +26,29 @@ def load_data(file_list: list): logger.debug("Starting evaluation.") model_path = "/opt/ml/processing/model/model.tar.gz" with tarfile.open(model_path) as tar: - tar.extractall(path=".") + + 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, path=".") logger.debug("Loading xgboost model.") model = pickle.load(open("xgboost-model", "rb")) diff --git a/build_pipeline/pipelines/evaluate.py b/build_pipeline/pipelines/evaluate.py index 00699bb..77fb2a8 100644 --- a/build_pipeline/pipelines/evaluate.py +++ b/build_pipeline/pipelines/evaluate.py @@ -20,7 +20,29 @@ logger.debug("Starting evaluation.") model_path = "/opt/ml/processing/model/model.tar.gz" with tarfile.open(model_path) as tar: - tar.extractall(path=".") + + 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, path=".") logger.debug("Loading xgboost model.") model = pickle.load(open("xgboost-model", "rb"))