From e76cfe36421192d017c8e9eeb9a24ae54dc153c5 Mon Sep 17 00:00:00 2001
From: TrellixVulnTeam <charles.mcfarland@trellix.com>
Date: Tue, 20 Dec 2022 00:16:10 +0000
Subject: [PATCH] Adding tarfile member sanitization to extractall()

---
 sdk/common/frontend.py | 21 ++++++++++++++++++++-
 sdk/merger/merge.py    | 21 ++++++++++++++++++++-
 2 files changed, 40 insertions(+), 2 deletions(-)

diff --git a/sdk/common/frontend.py b/sdk/common/frontend.py
index 0f64955..8f3f0ae 100644
--- a/sdk/common/frontend.py
+++ b/sdk/common/frontend.py
@@ -100,7 +100,26 @@ def _create_archive_dir(self):
             # This is vastly more efficient than accessing files one by one via
             # the tarfile API.
             with tarfile.open(self._archive) as archive:
-                archive.extractall(temp_dir)
+                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(archive, temp_dir)
             try:
                 yield temp_dir
             finally:
diff --git a/sdk/merger/merge.py b/sdk/merger/merge.py
index 317c96e..69e2479 100755
--- a/sdk/merger/merge.py
+++ b/sdk/merger/merge.py
@@ -25,7 +25,26 @@ def _open_archive(archive, directory):
         # This is vastly more efficient than accessing files one by one via
         # the tarfile API.
         with tarfile.open(archive) as archive_file:
-            archive_file.extractall(temp_dir)
+            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(archive_file, temp_dir)
         try:
             yield temp_dir
         finally: