Univention Corporate Server 4.3 erratum 44 (security)

This update addresses the following issues:
* libclamav/message.c allows remote attackers to cause a denial of service
  (out-of-bounds read) via a crafted e-mail message. (CVE-2017-6418)
* mspack/lzxd.c allows remote attackers to cause a denial of service
  (heap-based buffer overflow and application crash) or possibly have
  unspecified other impact via a crafted CHM file. (CVE-2017-6419)
* The wwunpack function allows remote attackers to cause a denial of service
  (use-after-free) via a crafted PE file with WWPack compression.
  (CVE-2017-6420)
* The cabd_read_string function allows remote attackers to cause a denial of
  service (stack-based buffer over-read and application crash) via a crafted
  CAB file. (CVE-2017-11423)
* Out-of-bounds access in the PDF parser (CVE-2018-0202)
* Out-of-bounds heap read in XAR parser (CVE-2018-1000085)