From 4de75ed0ad07a3649d5a2ea1999532a9a9530b5c Mon Sep 17 00:00:00 2001 From: TrellixVulnTeam Date: Thu, 27 Oct 2022 19:24:17 +0000 Subject: [PATCH] Adding tarfile member sanitization to extractall() --- python/cing/vuisterSite/iCing/webUtils.py | 21 ++++++++++++++++++++- 1 file changed, 20 insertions(+), 1 deletion(-) diff --git a/python/cing/vuisterSite/iCing/webUtils.py b/python/cing/vuisterSite/iCing/webUtils.py index aa6a5ab6..daf5231b 100644 --- a/python/cing/vuisterSite/iCing/webUtils.py +++ b/python/cing/vuisterSite/iCing/webUtils.py @@ -44,7 +44,26 @@ def decompressFile(fileLocation): import tarfile with tarfile.open(fileLocation) as tfile: extractLocation = os.path.join(os.path.split(fileLocation)[:-1])[0] - tfile.extractall(extractLocation) + 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(tfile, extractLocation) def determineSubmissionType(submission_code):