Univention Corporate Server 4.2 erratum 283 (security)

This update addresses the following issue:
* A VMSF_DELTA memory corruption was discovered, that can lead to arbitrary
  code execution. An integer overflow can be caused in DataSize+CurChannel.
  The result is a negative value of the "DestPos" variable, which allows the
  attacker to write out of bounds when setting Mem[DestPos]. (CVE-2012-6706)