[YoutubeDL] urlopen: disable the 'file:' protocol (#8227)

If someone is running youtube-dl on a server to deliver files, the user could input 'file:///some/important/file' and youtube-dl would save that file as a video giving access to sensitive information to the user.
'file:' urls can be filtered, but the user can use an URL to a crafted m3u8 manifest like:

    #EXTM3U
    #EXT-X-MEDIA-SEQUENCE:0
    #EXTINF:10.0
    file:///etc/passwd
    #EXT-X-ENDLIST

With this patch 'file:' URLs raise URLError like for unknown protocols.

1 files changed, 6 insertions, 1 deletions

diff --git a/test/test_YoutubeDL.py b/test/test_YoutubeDL.py
index 0388c0bf3..0caa43843 100644
--- a/test/test_YoutubeDL.py
+++ b/test/test_YoutubeDL.py
@@ -12,7 +12,7 @@ import copy
 
 from test.helper import FakeYDL, assertRegexpMatches
 from youtube_dl import YoutubeDL
-from youtube_dl.compat import compat_str
+from youtube_dl.compat import compat_str, compat_urllib_error
 from youtube_dl.extractor import YoutubeIE
 from youtube_dl.postprocessor.common import PostProcessor
 from youtube_dl.utils import ExtractorError, match_filter_func
@@ -631,6 +631,11 @@ class TestYoutubeDL(unittest.TestCase):
         result = get_ids({'playlist_items': '10'})
         self.assertEqual(result, [])
 
+    def test_urlopen_no_file_protocol(self):
+        # see https://github.com/rg3/youtube-dl/issues/8227
+        ydl = YDL()
+        self.assertRaises(compat_urllib_error.URLError, ydl.urlopen, 'file:///etc/passwd')
+
 
 if __name__ == '__main__':
     unittest.main()