Ubuntu Security Notice 544-1 – Samba developers discovered that nmbd could be made to overrun a buffer during the processing of GETDC logon server requests. When samba is configured as a Primary or Backup Domain Controller, a remote attacker could send malicious logon requests and possibly cause a denial of service. Alin Rad Pop of Secunia Research discovered that nmbd did not properly check the length of netbios packets. When samba is configured as a WINS server, a remote attacker could send multiple crafted requests resulting in the execution of arbitrary code with root privileges.
You can download this advisory from the following link: https://packetstormsecurity.com/files/download/60992/USN-544-1.txt
Source: https://packetstormsecurity.com/files/60992/Ubuntu-Security-Notice-544-1.html