CERTIFICATE_VERIFY_FAILED Windows only?

[Ulli Horlacher]

My program uses https and runs fine on Linux, but on Windows it crashes:

W10dev:/cygdrive/p: python fextasy.py -D
DEBUG(fextasy.py): verbose=0
DEBUG(fextasy.py): User-Agent: fextasy-20211127_1806 Windows 10.0.19041
DEBUG(fextasy.py): TCPCONNECT to fex.flupp.org:443
Traceback (most recent call last):
  File "P:\fextasy.py", line 1351, in <module>
    main()
  File "P:\fextasy.py", line 232, in main
    file = fexget('')
  File "P:\fextasy.py", line 622, in fexget
    if not http_connect(server,port):
  File "P:\fextasy.py", line 956, in http_connect
    if not tcp_connect(server,port): return
  File "P:\fextasy.py", line 973, in tcp_connect
    sock = context.wrap_socket(sock,server_hostname=host)
  File "C:\Users\admin\AppData\Local\Programs\Python\Python310\lib\ssl.py", line 512, in wrap_socket
    return self.sslsocket_class._create(
  File "C:\Users\admin\AppData\Local\Programs\Python\Python310\lib\ssl.py", line 1070, in _create
    self.do_handshake()
  File "C:\Users\admin\AppData\Local\Programs\Python\Python310\lib\ssl.py", line 1341, in do_handshake
    self._sslobj.do_handshake()
ssl.SSLCertVerificationError: [SSL: CERTIFICATE_VERIFY_FAILED] certificate verify failed: certificate has expired (_s
sl.c:997)


The sourcecode here is:

def tcp_connect(host,port):
  global sock

  message(f"D:TCPCONNECT to {host}:{port}")
  try:
    sock = socket.create_connection((host,port))
  except socket.error as e:
    message("E:cannot connect to %s:%d - %s" % (host,port,e.strerror))
    return False
  sock.settimeout(timeout)
  if port == 443:
    context = ssl.create_default_context()
    sock = context.wrap_socket(sock,server_hostname=host)
  return True



Google chrome and firefox both say the certifacte is valid:

https://fex.flupp.org/fop/U4xC4kz8/X-20211127192031.png

https://fex.flupp.org/fop/mBabXKSz/X-20211127192416.png

Why does Python complain (only on Windows!)?



-- 
Ullrich Horlacher              Server und Virtualisierung
Rechenzentrum TIK         
Universitaet Stuttgart         E-Mail: horlacher at tik.uni-stuttgart.de
Allmandring 30a                Tel:    ++49-711-68565868
70569 Stuttgart (Germany)      WWW:    http://www.tik.uni-stuttgart.de/