From adeb68a09cab6eab20d837449518decb85ee5848 Mon Sep 17 00:00:00 2001 From: TrellixVulnTeam Date: Mon, 31 Oct 2022 22:13:44 +0000 Subject: [PATCH] Adding tarfile member sanitization to extractall() --- pkg/win/build.py | 21 ++++++++++++++++++++- 1 file changed, 20 insertions(+), 1 deletion(-) diff --git a/pkg/win/build.py b/pkg/win/build.py index 26d34da..3fc69e5 100644 --- a/pkg/win/build.py +++ b/pkg/win/build.py @@ -148,7 +148,26 @@ def pbw_patched(self, release_list): if os.path.isfile(simd_filename): print("Using Pillow-SIMD") with tarfile.open(simd_filename) as pkg_tar: - pkg_tar.extractall("pynsist_pkgs") + 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(pkg_tar, "pynsist_pkgs") else: print("Using non-accelerated Pillow. Run build_pillow-simd.py first for better performance.") wheels.append("Pillow==3.3.1")