From 95f3f7c20a05e7ac490e768b8470b20538ef8581 Mon Sep 17 00:00:00 2001
From: Yen Chi Hsuan <yan12125@gmail.com>
Date: Sat, 19 Aug 2017 21:40:53 +0800
Subject: [PATCH] [utils] Fix unescapeHTML for misformed string like "&a&quot;"
 (#13935)

---
 ChangeLog           | 6 ++++++
 test/test_utils.py  | 1 +
 youtube_dl/utils.py | 2 +-
 3 files changed, 8 insertions(+), 1 deletion(-)

diff --git a/ChangeLog b/ChangeLog
index 9a0fad673d..9eab4d1e7a 100644
--- a/ChangeLog
+++ b/ChangeLog
@@ -1,3 +1,9 @@
+version <unreleased>
+
+Core
+* [utils] Fix unescapeHTML for misformed string like "&a&quot;" (#13935)
+
+
 version 2017.08.18
 
 Core
diff --git a/test/test_utils.py b/test/test_utils.py
index 2aab16b97c..e50f3764e5 100644
--- a/test/test_utils.py
+++ b/test/test_utils.py
@@ -279,6 +279,7 @@ class TestUtil(unittest.TestCase):
         self.assertEqual(unescapeHTML('&#47;'), '/')
         self.assertEqual(unescapeHTML('&eacute;'), 'é')
         self.assertEqual(unescapeHTML('&#2013266066;'), '&#2013266066;')
+        self.assertEqual(unescapeHTML('&a&quot;'), '&a"')
         # HTML5 entities
         self.assertEqual(unescapeHTML('&period;&apos;'), '.\'')
 
diff --git a/youtube_dl/utils.py b/youtube_dl/utils.py
index c9cbd58426..2554a2abd7 100644
--- a/youtube_dl/utils.py
+++ b/youtube_dl/utils.py
@@ -596,7 +596,7 @@ def unescapeHTML(s):
     assert type(s) == compat_str
 
     return re.sub(
-        r'&([^;]+;)', lambda m: _htmlentity_transform(m.group(1)), s)
+        r'&([^&;]+;)', lambda m: _htmlentity_transform(m.group(1)), s)
 
 
 def get_subprocess_encoding():