The best way to reduce the immediate risk associated with using an unsupported version of the software is to segregate the outdated software system from the main network. An unsupported software system may have unpatched vulnerabilities that could be exploited by attackers to compromise the system or access sensitive data. By isolating the system from the rest of the network, the organization can limit the exposure and impact of a potential breach. Verifying all patches have been applied to the outdated software system, closing all unused ports on the outdated software system and monitoring network traffic attempting to reach the outdated software system are also good practices, but they do not address the root cause of the risk, which is the lack of vendor support and updates. References:
* CISA Review Manual, 27th Edition, page 2951
* CISA Review Questions, Answers & Explanations Database - 12 Month Subscription