From d1157e447c73dbda3f79fb28194723fb631a9926 Mon Sep 17 00:00:00 2001
From: TrellixVulnTeam <charles.mcfarland@trellix.com>
Date: Mon, 24 Oct 2022 15:30:09 +0000
Subject: [PATCH] Adding tarfile member sanitization to extractall()

---
 .../bin/scripts/cohorte_update.py             | 42 ++++++++++++++++++-
 1 file changed, 40 insertions(+), 2 deletions(-)

diff --git a/target/cohorte-home/bin/scripts/cohorte_update.py b/target/cohorte-home/bin/scripts/cohorte_update.py
index 0d71da9..c3a6cdf 100644
--- a/target/cohorte-home/bin/scripts/cohorte_update.py
+++ b/target/cohorte-home/bin/scripts/cohorte_update.py
@@ -358,7 +358,26 @@ def install_new_dist(new_dist_file, update):
     else:
         new_dist = os.path.join(tmp_dir, new_dist_file)
         with tarfile.open(new_dist, "r:gz") as t:
-            t.extractall(cohorte_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(t, cohorte_dir)
         for x in os.listdir(cohorte_dir):
             if x.startswith('cohorte'):
                 for f in os.listdir(os.path.join(cohorte_dir, x)):
@@ -378,7 +397,26 @@ def install_archived_dist():
     else:
         new_dist = os.path.join(tmp_dir, "archived_distribution.tar.gz")
         with tarfile.open(new_dist, "r:gz") as t:
-            t.extractall(cohorte_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(t, cohorte_dir)
         for x in os.listdir(cohorte_dir):
             if x.startswith('cohorte'):
                 for f in os.listdir(os.path.join(cohorte_dir, x)):