[vk] Catch ownership confirmation request

youtube_dl/extractor/vk.py

@@ -156,6 +156,11 @@ def _real_extract(self, url):
         info_url = 'https://vk.com/al_video.php?act=show&al=1&module=video&video=%s' % video_id
         info_page = self._download_webpage(info_url, video_id)
 
+        if re.search(r'<!>/login\.php\?.*\bact=security_check', info_page):
+            raise ExtractorError(
+                'You are trying to log in from an unusual location. You should confirm ownership at vk.com to log in with this IP.',
+                expected=True)
+
         ERRORS = {
             r'>Видеозапись .*? была изъята из публичного доступа в связи с обращением правообладателя.<':
             'Video %s has been removed from public access due to rightholder complaint.',