It says to report this but so here I am ...

[adrianTNT]

youtube-dl --version 2018.09.26

youtube-dl --verbose --extract-audio https://www.youtube.com/watch?v=BCoP7G2K7Hc
[debug] System config: ['--prefer-free-formats']
[debug] User config: []
[debug] Custom config: []
[debug] Command-line args: ['--verbose', '--extract-audio', 'https://www.youtube.com/watch?v=BCoP7G2K7Hc']
[debug] Encodings: locale UTF-8, fs utf-8, out UTF-8, pref UTF-8
[debug] youtube-dl version 2018.09.26
[debug] Python version 3.4.8 (CPython) - Linux-3.10.0-862.3.3.el7.x86_64-x86_64-with-centos-7.5.1804-Core
[debug] exe versions: ffmpeg 2.8.14, ffprobe 2.8.14
[debug] Proxy map: {}
[youtube] BCoP7G2K7Hc: Downloading webpage
[youtube] BCoP7G2K7Hc: Downloading video info webpage
[youtube] {18} signature length 44.40, html5 player vflWnjS_n
[youtube] BCoP7G2K7Hc: Downloading player https://www.youtube.com/yts/jsbin/player-vflWnjS_n/en_US/base.js
ERROR: Signature extraction failed: Traceback (most recent call last):
  File "/usr/lib/python3.4/site-packages/youtube_dl/extractor/youtube.py", line 1221, in _decrypt_signature
    video_id, player_url, s
  File "/usr/lib/python3.4/site-packages/youtube_dl/extractor/youtube.py", line 1130, in _extract_signature_function
    res = self._parse_sig_js(code)
  File "/usr/lib/python3.4/site-packages/youtube_dl/extractor/youtube.py", line 1193, in _parse_sig_js
    jscode, 'Initial JS player signature function name', group='sig')
  File "/usr/lib/python3.4/site-packages/youtube_dl/extractor/common.py", line 977, in _search_regex
    raise RegexNotFoundError('Unable to extract %s' % _name)
youtube_dl.utils.RegexNotFoundError: Unable to extract Initial JS player signature function name; please report this issue on https://yt-dl.org/bug . Make sure you are using the latest version; see  https://yt-dl.org/update  on how to update. Be sure to call youtube-dl with the --verbose flag and include its complete output.
 (caused by RegexNotFoundError('Unable to extract \x1b[0;34mInitial JS player signature function name\x1b[0m; please report this issue on https://yt-dl.org/bug . Make sure you are using the latest version; see  https://yt-dl.org/update  on how to update. Be sure to call youtube-dl with the --verbose flag and include its complete output.',)); please report this issue on https://yt-dl.org/bug . Make sure you are using the latest version; see  https://yt-dl.org/update  on how to update. Be sure to call youtube-dl with the --verbose flag and include its complete output.
Traceback (most recent call last):
  File "/usr/lib/python3.4/site-packages/youtube_dl/extractor/youtube.py", line 1221, in _decrypt_signature
    video_id, player_url, s
  File "/usr/lib/python3.4/site-packages/youtube_dl/extractor/youtube.py", line 1130, in _extract_signature_function
    res = self._parse_sig_js(code)
  File "/usr/lib/python3.4/site-packages/youtube_dl/extractor/youtube.py", line 1193, in _parse_sig_js
    jscode, 'Initial JS player signature function name', group='sig')
  File "/usr/lib/python3.4/site-packages/youtube_dl/extractor/common.py", line 977, in _search_regex
    raise RegexNotFoundError('Unable to extract %s' % _name)
youtube_dl.utils.RegexNotFoundError: Unable to extract Initial JS player signature function name; please report this issue on https://yt-dl.org/bug . Make sure you are using the latest version; see  https://yt-dl.org/update  on how to update. Be sure to call youtube-dl with the --verbose flag and include its complete output.
Traceback (most recent call last):
  File "/usr/lib/python3.4/site-packages/youtube_dl/extractor/youtube.py", line 1221, in _decrypt_signature
    video_id, player_url, s
  File "/usr/lib/python3.4/site-packages/youtube_dl/extractor/youtube.py", line 1130, in _extract_signature_function
    res = self._parse_sig_js(code)
  File "/usr/lib/python3.4/site-packages/youtube_dl/extractor/youtube.py", line 1193, in _parse_sig_js
    jscode, 'Initial JS player signature function name', group='sig')
  File "/usr/lib/python3.4/site-packages/youtube_dl/extractor/common.py", line 977, in _search_regex
    raise RegexNotFoundError('Unable to extract %s' % _name)
youtube_dl.utils.RegexNotFoundError: Unable to extract Initial JS player signature function name; please report this issue on https://yt-dl.org/bug . Make sure you are using the latest version; see  https://yt-dl.org/update  on how to update. Be sure to call youtube-dl with the --verbose flag and include its complete output.

During handling of the above exception, another exception occurred:

Traceback (most recent call last):
  File "/usr/lib/python3.4/site-packages/youtube_dl/YoutubeDL.py", line 791, in extract_info
    ie_result = ie.extract(url)
  File "/usr/lib/python3.4/site-packages/youtube_dl/extractor/common.py", line 507, in extract
    ie_result = self._real_extract(url)
  File "/usr/lib/python3.4/site-packages/youtube_dl/extractor/youtube.py", line 1814, in _real_extract
    encrypted_sig, video_id, player_url, age_gate)
  File "/usr/lib/python3.4/site-packages/youtube_dl/extractor/youtube.py", line 1231, in _decrypt_signature
    'Signature extraction failed: ' + tb, cause=e)
youtube_dl.utils.ExtractorError: Signature extraction failed: Traceback (most recent call last):
  File "/usr/lib/python3.4/site-packages/youtube_dl/extractor/youtube.py", line 1221, in _decrypt_signature
    video_id, player_url, s
  File "/usr/lib/python3.4/site-packages/youtube_dl/extractor/youtube.py", line 1130, in _extract_signature_function
    res = self._parse_sig_js(code)
  File "/usr/lib/python3.4/site-packages/youtube_dl/extractor/youtube.py", line 1193, in _parse_sig_js
    jscode, 'Initial JS player signature function name', group='sig')
  File "/usr/lib/python3.4/site-packages/youtube_dl/extractor/common.py", line 977, in _search_regex
    raise RegexNotFoundError('Unable to extract %s' % _name)
youtube_dl.utils.RegexNotFoundError: Unable to extract Initial JS player signature function name; please report this issue on https://yt-dl.org/bug . Make sure you are using the latest version; see  https://yt-dl.org/update  on how to update. Be sure to call youtube-dl with the --verbose flag and include its complete output.
 (caused by RegexNotFoundError('Unable to extract \x1b[0;34mInitial JS player signature function name\x1b[0m; please report this issue on https://yt-dl.org/bug . Make sure you are using the latest version; see  https://yt-dl.org/update  on how to update. Be sure to call youtube-dl with the --verbose flag and include its complete output.',)); please report this issue on https://yt-dl.org/bug . Make sure you are using the latest version; see  https://yt-dl.org/update  on how to update. Be sure to call youtube-dl with the --verbose flag and include its complete output.

[vxbinaca]

upgrade your version to the latest

[adrianTNT]

By yum it says that 2018.09.26 is already latest version, is there a way to update by yum beyond that ?

Package youtube-dl-2018.09.26-1.el7.noarch already installed and latest version Nothing to do

Edit: I uninstalled my version with yum remove youtube-dl.noarch and installed manually with recommended commands, so easy :D

sudo curl -L https://yt-dl.org/downloads/latest/youtube-dl -o /usr/local/bin/youtube-dl
sudo chmod a+rx /usr/local/bin/youtube-dl

[vxbinaca]

Use pip3 to install it, it's uniform and timely updated and the recommended way to install it.