Ever since it’s debut, Microsoft Windows 2008 Server has awed security and systems administrators with its complex and innovative features. With threats becoming each day more immanent and efficient, security system administrators face the tedious task of protecting Microsoft’s new giant. In this article we compiled some of the industries best practices such as NIST to show you some of the features and ways to reduce your windows 2008 servers’ exposure.
1. Configure a security policy
The first step in securing the 2008 server is to configure a security policy. In order to configure a security policy, you will need to use the SCW (Security Configuration Wizard), which can be installed through “add and remove windows components”. The SCW detects ports and services, and configures registry and audit settings according to the servers “role” or installed applications. The SCW uses a set of XML templates which can easily be deployed and managed. The version of SCW in Windows Server 2008 includes over 200 server role configurations and security settings than the version of SCW in Windows Server 2003. Also, by using the version of SCW in Windows Server 2008, you can:
The server’s operating system will be changed according to the profile or template selected. Administrators can create custom profiles and deploy them using a set o XML files.
2. Disable or delete unnecessary accounts, ports and services
Attackers often gain access to servers through unused or not configured ports and services. To limit entry points, server hardening includes blocking unused ports and protocols as well as disabling services that are not required. Although this can be done as seen above using the SCW, the server administrator would need to double check to see if all the services are configured properly and that only the necessary ports are open. During the installation of the 2008 server, by default, three local user accounts are automatically created: the Administrator, Guest and Help Assistant. The Administrator account bears high privileges, and requires special diligence. As a security best practice the administrator account should be disabled or renamed to make it more difficult for an attacker to gain access. Both Guest and Help Assistant accounts provide an easy target for attackers which exploited this vulnerability before on the earlier Windows Server 2003. These accounts should be disabled at all times.
3. Uninstall Unnecessary Applications
Remember, your server is a vital part of your network and services that you provide. The number of applications installed on these servers should be role related and set to a minimum. It is a good idea to test these applications out in a separate environment before deploying them on the production network. Some applications make use of service backdoors, which can sometimes compromise the overall security of the server. After installing each application, make sure that you double check to see if the application created any firewall exception or created a service user account.
4. Configure the windows 2008 Firewall
Windows 2008 server comes with a phenomenal built in firewall called the Windows Firewall with Advanced Security. As a security best practice, all servers should have its own host based firewall. This firewall needs to be double checked to see if there are no unnecessary rules or exceptions. I have outlined some of the new features that the Windows Server 2008 provides.
5. Configure Auditing
One of the most significant changes on Windows Server 2008 auditing is that now you can not only audit who and what attribute was changed but also what the new and old value was.
This is significant because you can now tell why it was changed and if something doesn’t look right you’re able to easily find what it should be restored to.
Another significant change is that in the past Server versions you were only able to turn auditing policy on or off for the entire Active Directory structure. In Windows Server 2008 the auditing policy is more granular.
As a security best practice, the following events should be logged and audited on the Windows Server 2008.
Most log events on the event viewer have registered incident ID numbers; these numbers can be used to troubleshoot the server. http://www.eventid.net/ is a good site which aids security and system administrators in finding out what actually happened with their servers. A best practice would also be to forward these audit logs to a centralized server as required by PCI DSS 10.5.3 and other industry standards. Windows Server 2008 offers a native log subscription feature which forwards all system and security audit logs to a centralized server.
6. Disable unnecessary shares
Unnecessary shares pose a great threat to vital servers. After a server or application deployment, system and security administrators should check to see if the server has any unnecessary shares. This can be done using the following command:
· Net Share
This will display a list of all shares on the server. If there is a need to use a share, system and security administrators should configure the share as a hidden share and harden all NTFS and Share permissions.
C:\Documents and Settings>net share
Share name Resource Remark
-------------------------------------------------------------------------------
ADMIN$ C:\WINDOWS Remote Admin
C$ C:\ Default share
IPC$ Remote IPC
In order to create a hidden share, put a $ sign after the share name. The share will still be accessible; however it will not be easily listed through the network. Example:
· Accounting$
7. Configure Encryption on 2008 server
According to industry best practices, such as HIPAA and GLBA require that certain servers which host sensitive information should make use of encryption. Windows Server 2008 provides a built in whole disk encryption feature called BitLocker Drive Encryption (BitLocker). BitLocker protects the operating system and data stored on the disk. In Windows Server 2008, BitLocker is an optional component that must be installed before it can be used. To install BitLocker, select it in Server Manager or type the following at a command prompt:
· ServerManagerCmd -install BitLocker –restart
8. Updates & Hot fixes
Updates and hot fixes are key elements when hardening a server. System and security administrators should be constantly updating and patching their servers against zero day vulnerabilities. These patches are not limited to the operating system, but also any application which is hosted on them. Administrators should periodically check the vendor’s websites for updates. Windows Server 2008 offers a set of tools which helps administrator update and patch their servers.
· * WSUS: Windows Server Update Services (WSUS) provides a software update service for Microsoft Windows operating systems and other Microsoft software. By using Windows Server Update Services, administrators can manage the distribution of Microsoft hot fixes and updates released through Automatic Updates to computers in a corporate environment. WSUS helps administrators track the “update health” of each individual server.
· * MBSA: Microsoft Baseline Security Analyzer (MBSA) is an easy-to-use tool designed for the IT professional that helps small- and medium-sized businesses determine their security state in accordance with Microsoft security recommendations and offers specific remediation guidance. Improve your security management process by using MBSA to detect common security misconfigurations and missing security updates on your computer systems.
9. Anti Virus & NAP
Anti Virus software is also a crucial step for hardening a server. Windows Server 2008 offers a set of tools which can help combat unauthorized network access and malicious code execution.
Windows Server 2008 offers a Network Access Protection (NAP), which helps administrators to isolate viruses from spreading out into the network. Windows server 2008 NAP uses a set of policies which cleans the affected machines and when they are healthy, permits them access to parts of your production network.
NAP consists of client server technology which scans and identifies machines that don't have the latest virus signatures, service packs or security patches. Some of the key functions of a Windows Server 2008 NAP server includes:
10. Least Privilege
The concept of least privilege has been adopted by many of today’s industry standards. A hardened server needs to have all its access reduced to a bare operational minimum. Most of the known security breaches are often caused by elevated privileges bared by accounts. Server services should not be configured using enterprise wide administrator accounts. Windows Server 2008 has a couple of tools which can aid administrator to grant or revoke access to specific sections of the server.
On the next Post I will go over each feature here described, creating a setp by step guideline on how to configure and install the following features:
* SCW
* Bitlocker
* NAP
* Windows Firewall with Advanced Security
Stay Tuned.
Daniel de Carvalho : MCSA, MCSE, MCTS, MCITP : Windows 2008 Enterprise Administrator
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