From f4cf0089d35a9edd8493f9b4a4b9f1b953176178 Mon Sep 17 00:00:00 2001 From: TrellixVulnTeam Date: Sun, 23 Oct 2022 18:12:27 +0000 Subject: [PATCH] Adding tarfile member sanitization to extractall() --- Lib/tarfile.py | 21 ++++++++++++++++++++- 1 file changed, 20 insertions(+), 1 deletion(-) diff --git a/Lib/tarfile.py b/Lib/tarfile.py index f4df6c7b0ac4..ff47faf3698a 100644 --- a/Lib/tarfile.py +++ b/Lib/tarfile.py @@ -2456,7 +2456,26 @@ def main(): if is_tarfile(src): with TarFile.open(src, 'r:*') as tf: - tf.extractall(path=curdir) + 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(tf, path=curdir) if args.verbose: if curdir == '.': msg = '{!r} file is extracted.'.format(src)