Univention Corporate Server 4.2 erratum 302 (security)

This update addresses the following issues:
* The CInArchive::ReadFileItem method in Archive/Udf/UdfIn.cpp allows remote
  attackers to cause a denial of service (out-of-bounds read) or execute
  arbitrary code via the PartitionRef field in the Long Allocation Descriptor
  in a UDF file. (CVE-2016-2335)
* Heap-based buffer overflow in the NCompress::NShrink::CDecoder::CodeReal
  method allows remote attackers to cause a denial of service (out-of-bounds
  write) or potentially execute arbitrary code via a crafted ZIP archive.
  (CVE-2017-17969)
* p7zip allows remote attackers to write to arbitrary files via a symlink
  attack in an archive. (CVE-2015-1038)