Security update for clamav (moderate)

This update for clamav fixes the following issues:

clamav was updated to version 0.100.2:

• CVE-2018-15378: Vulnerability in ClamAV’s MEW unpacking feature that
  could allow an unauthenticated, remote attacker to cause a denial of
  service (DoS) condition on an affected device. (bsc#1110723)

• CVE-2018-14680, CVE-2018-14681, CVE-2018-14682: more fixes for embedded
  libmspack. (bsc#1103040)

• Make freshclam more robust against lagging signature mirrors.

• On-Access "Extra Scanning", an opt-in minor feature of OnAccess scanning
  on Linux systems, has been disabled due to a known issue with resource
  cleanup OnAccessExtraScanning will be re-enabled in a future release
  when the issue is resolved. In the mean-time, users who enabled the
  feature in clamd.conf will see a warning informing them that the feature
  is not active. For details, see:
  <a href=“https://bugzilla.clamav.net/show_bug.cgi?id=12048”>https://bugzilla.clamav.net/show_bug.cgi?id=12048</a>

• Restore exit code compatibility of freshclam with versions before
  0.100.0 when the virus database is already up to date (bsc#1104457).

This update was imported from the SUSE:SLE-12:Update update project.