Check the validity of the SSL certificates failure

At last self check i got an certificate verify error. This is an UCS Slave Server. Here is the whole error log:
UCS Version 4.4-7 errata868

############################ Start 02_certificate_check ###########################
## Check failed: 02_certificate_check - Überprüfe Gültigkeit der SSL Zertifikate ##
Traceback (most recent call last):
  File "/usr/lib/python2.7/dist-packages/univention/management/console/modules/diagnostic/__init__.py", line 280, in execute
    result = execute(umc_module, **kwargs)
  File "/usr/lib/python2.7/dist-packages/univention/management/console/modules/diagnostic/plugins/02_certificate_check.py", line 286, in run
    cert_verify = list(verify_from_master(configRegistry.get('ldap/master'), all_certificates))
  File "/usr/lib/python2.7/dist-packages/univention/management/console/modules/diagnostic/plugins/02_certificate_check.py", line 265, in verify_from_master
    with download_tempfile(root_ca_uri) as root_ca, download_tempfile(crl_uri) as crl:
  File "/usr/lib/python2.7/contextlib.py", line 17, in __enter__
    return self.gen.next()
  File "/usr/lib/python2.7/dist-packages/univention/management/console/modules/diagnostic/plugins/02_certificate_check.py", line 238, in download_tempfile
    response = requests.get(url, stream=True)
  File "/usr/lib/python2.7/dist-packages/requests/api.py", line 70, in get
    return request('get', url, params=params, **kwargs)
  File "/usr/lib/python2.7/dist-packages/requests/api.py", line 56, in request
    return session.request(method=method, url=url, **kwargs)
  File "/usr/lib/python2.7/dist-packages/requests/sessions.py", line 488, in request
    resp = self.send(prep, **send_kwargs)
  File "/usr/lib/python2.7/dist-packages/requests/sessions.py", line 630, in send
    history = [resp for resp in gen] if allow_redirects else []
  File "/usr/lib/python2.7/dist-packages/requests/sessions.py", line 190, in resolve_redirects
    **adapter_kwargs
  File "/usr/lib/python2.7/dist-packages/requests/sessions.py", line 609, in send
    r = adapter.send(request, **kwargs)
  File "/usr/lib/python2.7/dist-packages/requests/adapters.py", line 497, in send
    raise SSLError(e, request=request)
SSLError: ("bad handshake: Error([('SSL routines', 'tls_process_server_certificate', 'certificate verify failed')],)",)
############################# End 02_certificate_check ############################

What i have found:



All 3 points are ok. So it look likes an programerror from UCS.

Can anyone help to solve this issue?

Best Regards
boospy