Univention Corporate Server 4.2 erratum 564 (extended maintenance)

This update addresses the following issues:
* Nullsoft Scriptable Install System (NSIS) before 2.49 uses temporary folder
  locations that allow unprivileged local users to overwrite files. This
  allows a local attack in which either a plugin or the uninstaller can be
  replaced by a Trojan horse program. (CVE-2015-9267)
* Nullsoft Scriptable Install System (NSIS) before 2.49 has unsafe implicit
  linking against Version.dll. In other words, there is no protection
  mechanism in which a wrapper function resolves the dependency at an
  appropriate time during runtime. (CVE-2015-9268)