Univention Corporate Server 4.4 erratum 645 (security)

This update addresses the following issues:
* A client combining the 'ASQ' and 'VLV' LDAP
  controls can cause a NULL pointer de-reference and
  further combinations with the LDAP paged_results
  feature can give a use-after-free in Samba's AD DC
  LDAP server. (CVE-2020-10730)
* Compression of replies to NetBIOS over TCP/IP
  name resolution and DNS packets (which can be
  supplied as UDP requests) can be abused to
  consume excessive amounts of CPU on the Samba
  AD DC (only). (CVE-2020-10745)
* The use of the paged_results or VLV controls against
  the Global Catalog LDAP server on the AD DC will cause
  a use-after-free. (CVE-2020-10760)
* The AD DC NBT server in Samba 4.0 will enter a
  CPU spin and not process further requests
  once it receives a empty (zero-length) UDP
  packet to port 137. (CVE-2020-14303)