bất kỳ tài khoản không cần thiết từ vai trò máy chủ quản trị hệ thống và khóa tài khoản sa. Giả sử bạn chọn chế độ xác thực Windows trong quá trình cài đặt (hoặc chuyển sang chế độ đó kể từ đó), bước đầu tiên của bạn | Dangers Associated with Mail Service Attacks 81 TIP In order to minimize the chances of a successful directory harvest attack you should take the time to perform some market research. Many applications such as Symantec Brightmail Gateway and Cisco Ironport exist today that have the capability to recognize a directory harvest attack and stop it in its tracks. Since in most cases directory harvest attacks originate from the Internet as the administrator you can be proactive by deploying an application or appliance in your perimeter network that has the capability to detect and stop directory harvest attacks. Most of these appliances are intended to be the first point of connection for any inbound messaging traffic and in addition to detecting directory harvest attacks should also be equipped to run antivirus and spam checking as well as be able to recognize and react to other attack types such as DoS attacks. Scenario 2 SMTP Auth Attacks Secure-by-default has been mentioned on more than one occasion here and in the world of Exchange Server each new version introduces changes that continue to revamp the security by default landscape. One of the Exchange 2007 security modifications came as a result of the SMTP Auth attack which became common and quite successful when used against Internet facing Exchange 2003 servers. By default with an out-of-the-box configuration Exchange 2003 was configured to deny relay attempts. This was a step in the right direction with one small caveat Exchange 2003 would allow relay for any authenticated user. So enter the SMTP Auth attack. By connecting to an Exchange server and launching a password attack against any of the built-in user accounts an attacker would eventually obtain authenticated user credentials. Since authenticated users were allowed to relay the attacker now had the ability to send as many e-mail messages as desired to the Internet through the compromised Exchange server. SMTP Auth attacks
