The RPC code generator in Samba 3.x before 3.4.16, 3.5.x before 3.5.14, and 3.6.x before 3.6.4 does not implement validation of an array length in a manner consistent with validation of array memory allocation, which allows remote attackers to execute arbitrary code via a crafted RPC call. Successful exploitation of this vulnerability allows remote code execution as the "root" user from an anonymous connection.