Within an organization, every system on the network has some sort of risk associated with it, whether supported or not. There are still a number of organizations that are still using Windows 2000. Why? Maybe they do not have the budget to do a full upgrade to the latest and greatest OS; maybe there are other projects that have a higher priority. Either way, it is up to the organization to determine the acceptable risk for continued use of Windows 2000-based systems.
Once again, every system on the network has some sort of risk. But these systems do not have the same importance or sensitivity. Organizations should review their systems where Window 2000 is installed, and determine the risk of these systems. Systems should be ranked at three levels: low, medium and high risk. There are fundamental settings that can be implemented at all three levels of risk. In some cases, Windows 2000-based systems could be used with an acceptable level of risk.
I do not recommend that organizations use what I am about to say as an excuse to keep Windows 2000 in their environment. However, if Windows 2000 is a necessity at this time within your environment, below are some techniques you can implement, depending on the risk of the system.
For systems that are lower risk:
- Aggressively monitor for vulnerabilities and active threats targeting Windows 2000-based systems. It is recommended that organizations monitor Microsoft’s monthly patch releases for vulnerabilities that affect multiple versions of Windows, paying close attention to patches that affect Windows XP and Windows 2003 Server.
- Continue to run software such as a local firewall, antivirus, anti-spyware, and host-based IPS.
- Whatever elements installed on the Windows 2000-based system should be patched.
- Implement some sort of incident response plan to be ready in the event a breach occurs.
- Have a plan to migrate to a new server operating system if necessary.
To make it harder to reach the Windows 2000 systems:
- Segment the Windows 2000 systems from the rest of the network. Only specified services should be able to access these systems.
- Whitelist and restrict access to only users who need access.
To reduce the attack surface of the Windows 2000 system, remove any unnecessary drives, services, and support modules.
For systems that are medium risk:
- Implement all of the steps mentioned for lower risk systems.
- Reduce the ability to place arbitrary code on the system.
- Applications that are allowed to run on the system should be whitelisted.
- Full auditing and logging should be implemented on Windows 2000 systems. The logs should be sent to a SIEM.
- A File Integrity Monitor (FIM) should be implemented to help with in depth monitoring.
For systems that are high risk:
- Implement all of the steps mentioned for lower and medium risk systems.
- It is recommended that the Windows 2000 system’s behavior be whitelisted through a host-based IPS.
- Buffer overflow protection should be implemented for in depth defense for Windows 2000.
- If there are Windows 2000-based server applications running, the application input from users should be whitelisted through an application firewall.
- SecureState recommends that application data be stored to another, more secure system.
- If the Windows 2000-based systems appears to have been breached, the network and traffic should be restricted and monitored.
- Monitor and restrict a sensitive applications output if it appears the system has been breached.
There are things that can be done to help prevent data leakage with Windows 200-based systems. In my opinion, Windows 2000 should not be used in any environment. The things I mentioned in this blog will help security, but not solve it.