Updated samba packages fix security vulnerability

A flaw was found in the way Samba handled PAC (Privilege Attribute Certificate) checksums. A remote, authenticated attacker could use this flaw to crash the winbindd process (CVE-2016-2126). Jann Horn discovered that Samba incorrectly handled symlinks. An authenticated remote attacker could use this issue to access files on the server outside of the exported directories (CVE-2017-2619). A remote code execution flaw was found in Samba. A malicious authenticated samba client, having write access to the samba share, could use this flaw to execute arbitrary code as root (CVE-2017-7494).