Merge pull request #268 from TrellixVulnTeam/master

CVE-2007-4559 Patch

src/target.py

@@ -836,7 +836,23 @@ def read(self,mvals,AGrad=False,AHess=False):
 
     def get(self,mvals,AGrad=False,AHess=False):
         with tarfile.open("target_result.tar.bz2", "r") as tar:
-            tar.extractall()
+            # Added by vulnerability checker to guard against directory traversal attack
+            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)
+        # Remove the target_result archive as it's not needed anymore.
+        os.unlink("target_result.tar.bz2")
         with open('indicate.log', 'r') as f:
             self.remote_indicate = f.read()
         return lp_load('objective.p')