Add override for generic vulnerability

Authored by: Grub4K

devscripts/changelog_override.json

@@ -109,5 +109,10 @@
         "action": "add",
         "when": "1d03633c5a1621b9f3a756f0a4f9dc61fab3aeaa",
         "short": "[priority] **The release channels have been adjusted!**\n\t* [`master`](https://github.com/yt-dlp/yt-dlp-master-builds) builds are made after each push, containing the latest fixes (but also possibly bugs). This was previously the `nightly` channel.\n\t* [`nightly`](https://github.com/yt-dlp/yt-dlp-nightly-builds) builds are now made once a day, if there were any changes."
+    },
+    {
+        "action": "add",
+        "when": "f04b5bedad7b281bee9814686bba1762bae092eb",
+        "short": "[priority] Security: [[CVE-2023-46121](https://cve.mitre.org/cgi-bin/cvename.cgi?name=CVE-2023-46121)] Patch [Generic Extractor MITM Vulnerability via Arbitrary Proxy Injection](https://github.com/yt-dlp/yt-dlp/security/advisories/GHSA-3ch3-jhc6-5r8x)\n\t- Disallow smuggling of arbitary `http_headers`; extractors now only use specific headers"
     }
 ]

yt_dlp/extractor/cbc.py

@@ -1,8 +1,9 @@
-import re
-import json
 import base64
+import json
+import re
 import time
 import urllib.parse
+import xml.etree.ElementTree
 
 from .common import InfoExtractor
 from ..compat import (
@@ -387,7 +388,7 @@ class CBCGemIE(InfoExtractor):
         url = re.sub(r'(Manifest\(.*?),format=[\w-]+(.*?\))', r'\1\2', base_url)
 
         secret_xml = self._download_xml(url, video_id, note='Downloading secret XML', fatal=False)
-        if secret_xml is None:
+        if not isinstance(secret_xml, xml.etree.ElementTree.Element):
             return
 
         for child in secret_xml:

yt_dlp/extractor/common.py

@@ -2225,7 +2225,9 @@ class InfoExtractor:
             mpd_url, video_id,
             note='Downloading MPD VOD manifest' if note is None else note,
             errnote='Failed to download VOD manifest' if errnote is None else errnote,
-            fatal=False, data=data, headers=headers, query=query) or {}
+            fatal=False, data=data, headers=headers, query=query)
+        if not isinstance(mpd_doc, xml.etree.ElementTree.Element):
+            return None
         return int_or_none(parse_duration(mpd_doc.get('mediaPresentationDuration')))
 
     @staticmethod

yt_dlp/extractor/mtv.py

@@ -1,4 +1,5 @@
 import re
+import xml.etree.ElementTree
 
 from .common import InfoExtractor
 from ..compat import compat_str
@@ -137,7 +138,7 @@ class MTVServicesInfoExtractor(InfoExtractor):
         mediagen_doc = self._download_xml(
             mediagen_url, video_id, 'Downloading video urls', fatal=False)
 
-        if mediagen_doc is None:
+        if not isinstance(mediagen_doc, xml.etree.ElementTree.Element):
             return None
 
         item = mediagen_doc.find('./video/item')

yt_dlp/extractor/nbc.py

@@ -1,6 +1,7 @@
 import base64
 import json
 import re
+import xml.etree.ElementTree
 
 from .common import InfoExtractor
 from .theplatform import ThePlatformIE, default_ns
@@ -803,6 +804,8 @@ class NBCStationsIE(InfoExtractor):
             smil = self._download_xml(
                 f'https://link.theplatform.com/s/{pdk_acct}/{player_id}', video_id,
                 note='Downloading SMIL data', query=query, fatal=is_live)
+            if not isinstance(smil, xml.etree.ElementTree.Element):
+                smil = None
         subtitles = self._parse_smil_subtitles(smil, default_ns) if smil is not None else {}
         for video in smil.findall(self._xpath_ns('.//video', default_ns)) if smil is not None else []:
             info['duration'] = float_or_none(remove_end(video.get('dur'), 'ms'), 1000)

yt_dlp/extractor/slideslive.py

@@ -1,5 +1,6 @@
 import re
 import urllib.parse
+import xml.etree.ElementTree
 
 from .common import InfoExtractor
 from ..utils import (
@@ -469,11 +470,12 @@ class SlidesLiveIE(InfoExtractor):
             slides = self._download_xml(
                 player_info['slides_xml_url'], video_id, fatal=False,
                 note='Downloading slides XML', errnote='Failed to download slides info')
-            slide_url_template = 'https://cdn.slideslive.com/data/presentations/%s/slides/big/%s%s'
-            for slide_id, slide in enumerate(slides.findall('./slide') if slides is not None else [], 1):
-                slides_info.append((
-                    slide_id, xpath_text(slide, './slideName', 'name'), '.jpg',
-                    int_or_none(xpath_text(slide, './timeSec', 'time'))))
+            if isinstance(slides, xml.etree.ElementTree.Element):
+                slide_url_template = 'https://cdn.slideslive.com/data/presentations/%s/slides/big/%s%s'
+                for slide_id, slide in enumerate(slides.findall('./slide')):
+                    slides_info.append((
+                        slide_id, xpath_text(slide, './slideName', 'name'), '.jpg',
+                        int_or_none(xpath_text(slide, './timeSec', 'time'))))
 
         chapters, thumbnails = [], []
         if url_or_none(player_info.get('thumbnail')):