Secunia Research reported a vulnerability that allows for the execution of arbitrary code in nmbd. This defect is only be exploited when the “domain logons” parameter has been enabled in smb.conf. Samba versions 3.0.0 through 3.0.27a are affected.
You can download this advisory from the following link: https://packetstormsecurity.com/files/download/61655/samba-overrun.txt
Source: https://packetstormsecurity.com/files/61655/samba-overrun.txt.html