From cc18687ee4ccb22843f8a95785c7b7c5ced3497c Mon Sep 17 00:00:00 2001 From: TrellixVulnTeam Date: Wed, 2 Nov 2022 23:29:24 +0000 Subject: [PATCH] Adding tarfile member sanitization to extractall() --- data/corpus_downloaders.py | 21 ++++++++++++++++++++- 1 file changed, 20 insertions(+), 1 deletion(-) diff --git a/data/corpus_downloaders.py b/data/corpus_downloaders.py index 3600544..368b926 100644 --- a/data/corpus_downloaders.py +++ b/data/corpus_downloaders.py @@ -90,4 +90,23 @@ def extract(self, path='.'): self.extract_path = os.path.join(path, 'clean_corpus') os.makedirs(path, exist_ok=True) with tarfile.open(self.download_path, "r:bz2") as tar: - tar.extractall(self.extract_path) + 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, self.extract_path)