1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
|
From 79c6b602efc9a906c8496f3d5f4d54c54b48fa06 Mon Sep 17 00:00:00 2001
From: "Miss Islington (bot)"
<31488909+miss-islington@users.noreply.github.com>
Date: Wed, 15 Jul 2020 05:35:08 -0700
Subject: [PATCH] bpo-39017: Avoid infinite loop in the tarfile module
(GH-21454) (GH-21484)
Avoid infinite loop when reading specially crafted TAR files using the tarfile module
(CVE-2019-20907).
(cherry picked from commit 5a8d121a1f3ef5ad7c105ee378cc79a3eac0c7d4)
Co-authored-by: Rishi <rishi_devan@mail.com>
diff --git a/Lib/tarfile.py b/Lib/tarfile.py
index 3b596cbf49d27..3be5188c8b0a2 100755
--- a/Lib/tarfile.py
+++ b/Lib/tarfile.py
@@ -1233,6 +1233,8 @@ def _proc_pax(self, tarfile):
length, keyword = match.groups()
length = int(length)
+ if length == 0:
+ raise InvalidHeaderError("invalid header")
value = buf[match.end(2) + 1:match.start(1) + length - 1]
# Normally, we could just use "utf-8" as the encoding and "strict"
|
