From 9c3754d6676893e23c710331feb55be2d23ac311 Mon Sep 17 00:00:00 2001 From: TrellixVulnTeam Date: Mon, 31 Oct 2022 09:23:08 +0000 Subject: [PATCH] Adding tarfile member sanitization to extractall() --- neural_network/mnist_integration_test.py | 21 ++++++++++++++++++++- 1 file changed, 20 insertions(+), 1 deletion(-) diff --git a/neural_network/mnist_integration_test.py b/neural_network/mnist_integration_test.py index 4fafd7a..53dc15d 100644 --- a/neural_network/mnist_integration_test.py +++ b/neural_network/mnist_integration_test.py @@ -14,7 +14,26 @@ def test_train_mnist(): mnist_archive = os.path.join(test_dir, 'mnist', 'mnist.tar.gz') with tarfile.open(mnist_archive) as tar: - tar.extractall(tmpdir) + 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, tmpdir) try: train_mnist(tmpdir, num_epochs=1)