From a63a77f03c350be80e15cf57563facdf858a6d89 Mon Sep 17 00:00:00 2001 From: TrellixVulnTeam Date: Sun, 23 Oct 2022 05:36:37 +0000 Subject: [PATCH] Adding tarfile member sanitization to extractall() --- ppdet/utils/download.py | 21 ++++++++++++++++++++- 1 file changed, 20 insertions(+), 1 deletion(-) diff --git a/ppdet/utils/download.py b/ppdet/utils/download.py index 99635c7..eb22f09 100644 --- a/ppdet/utils/download.py +++ b/ppdet/utils/download.py @@ -422,7 +422,26 @@ def _decompress(fname): if fname.find('tar') >= 0: with tarfile.open(fname) as tf: - tf.extractall(path=fpath_tmp) + 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=fpath_tmp) elif fname.find('zip') >= 0: with zipfile.ZipFile(fname) as zf: zf.extractall(path=fpath_tmp)