From 55be76d02d3cf26745714834f76b1c86efc4bcee Mon Sep 17 00:00:00 2001 From: TrellixVulnTeam Date: Wed, 16 Nov 2022 18:33:38 +0000 Subject: [PATCH] Adding tarfile member sanitization to extractall() --- src/piotr/package.py | 21 ++++++++++++++++++++- 1 file changed, 20 insertions(+), 1 deletion(-) diff --git a/src/piotr/package.py b/src/piotr/package.py index a0a8c0f..103f9a6 100644 --- a/src/piotr/package.py +++ b/src/piotr/package.py @@ -127,7 +127,26 @@ def package_import(package_path): __remove_dir(temp_dir) raise BadPackageError() # Decompress - pack.extractall(temp_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(pack, temp_dir) # Then proceed with decompressed package. # First, we load the config.yaml file