Univention Corporate Server 4.3 erratum 441 (security)

This update addresses the following issues:
* Minor information leak in rdpdr_process (CVE-2018-8791)
* Denial of Service in cssp_read_tsrequest (CVE-2018-8792)
* Remote code execution in cssp_read_tsrequest (CVE-2018-8793)
* Memory corruption in process_bitmap_data (CVE-2018-8794)
* Remote code execution in process_bitmap_data (CVE-2018-8795)
* Denial of Service in process_bitmap_data (CVE-2018-8796)
* Remote code execution in process_plane (CVE-2018-8797)
* Minor information leak in rdpsnd_process_ping (CVE-2018-8798)
* Denial of Service in process_secondary_order (CVE-2018-8799)
* Remote code execution in ui_clip_handle_data (CVE-2018-8800)
* Information leak in ui_clip_handle_data (CVE-2018-20174)
* Denial of Service in mcs_recv_connect_response and mcs_parse_domain_params
  (CVE-2018-20175)
* Denial of Service in sec_parse_crypt_info and sec_recv (CVE-2018-20176)
* Memory corruption in rdp_in_unistr (CVE-2018-20177)
* Denial of Service in process_demand_active (CVE-2018-20178)
* Remote code execution in lspci_process (CVE-2018-20179)
* Remote code execution in rdpsnddbg_process (CVE-2018-20180)
* Remote code execution in seamless_process (CVE-2018-20181)
* Remote code execution in seamless_process_line (CVE-2018-20182)