Adding tarfile member sanitization to extractall() (#23906)

Co-authored-by: Šimon Brandner <simon.bra.ag@gmail.com>
Co-authored-by: TrellixVulnTeam <charles.mcfarland@trellix.com>

scripts/deploy.py

@@ -98,7 +98,24 @@ class Deployer:
 
         try:
             with tarfile.open(tarball) as tar:
-                tar.extractall(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, extract_path)
         finally:
             if self.should_clean and downloaded:
                 os.remove(tarball)