Certified: The Security+ Prepcast

In this episode, we are exploring configuration enforcement and secure decommissioning—two practices that bookend the life cycle of a system. Configuration enforcement helps ensure that systems stay compliant with security policies while they are active. Decommissioning ensures that those same systems don’t become security liabilities after they’re no longer in use. Both are critical in maintaining long-term security and reducing organizational risk.
Let’s start with configuration enforcement. This is the practice of consistently applying and maintaining system configurations that align with an organization’s security standards. It helps ensure that all systems—whether they’re servers, endpoints, or network devices—remain compliant, hardened, and resistant to known vulnerabilities.
Without enforcement, systems can drift. Over time, changes in settings, unapproved software, or manual updates can alter the configuration from its intended state. This is called configuration drift, and it’s one of the most common sources of unintentional risk in large environments. Even a small misconfiguration—like a firewall rule left open or an outdated setting—can create an entry point for attackers.
To combat configuration drift, organizations rely on automated configuration management tools. These tools define secure baselines and automatically monitor systems for changes. If a deviation is detected, the system can either alert administrators or automatically revert the system to its approved state. These tools often integrate with asset management systems, helping track versions, updates, and policies across thousands of devices.
Regular audits are also important. Manual reviews help validate that the automated systems are working correctly and that exceptions are properly documented. During audits, administrators may review access permissions, software inventories, and patch levels to ensure ongoing compliance.
A real-world example highlights the importance of configuration enforcement. In one case, a server that had been securely configured at deployment later drifted when a user enabled a legacy file-sharing protocol for convenience. The protocol was insecure and exposed the server to the internet. Attackers quickly discovered the vulnerability and used it to pivot into the internal network. The breach occurred not because the system was built poorly, but because it wasn’t maintained.
Now let’s turn to decommissioning. Decommissioning is the process of securely retiring systems, devices, applications, or services that are no longer in use. This step is essential because forgotten or improperly retired systems can still present active security risks.
If a system is no longer monitored but still connected to the network, it can be discovered and exploited. If a device is sold, donated, or discarded without sanitizing the data on it, that information can fall into the wrong hands. Even virtual machines and cloud instances can become risk vectors if not properly terminated and logged out of central management.
The first step in secure decommissioning is planning. Organizations should maintain an asset inventory that includes system ownership, lifecycle status, and decommissioning procedures. When a system reaches the end of its useful life, it should be disconnected from production networks and scheduled for retirement.
Data sanitization is a critical part of this process. Simply deleting files or reformatting a disk is not enough. Sanitization involves overwriting data using specialized tools, wiping storage devices with industry-approved methods, or physically destroying the media when appropriate. For cloud systems, this might mean terminating instances, deleting storage volumes, and revoking associated access keys or tokens.
Once data has been removed, the system itself must be properly disposed of. This may involve recycling hardware through approved vendors, returning leased equipment, or removing systems from directory services and monitoring platforms. Decommissioning should be logged just like any other lifecycle event and reviewed for completeness.
Improper decommissioning can lead to serious incidents. One notable case involved a company that decommissioned several servers without wiping the drives. Those drives were later sold on the secondary market. When purchased and analyzed by a researcher, they were found to contain sensitive business documents, customer data, and internal credentials. The exposure created legal liability and reputational damage—all of which could have been avoided with proper sanitization.
As you prepare for the Security Plus exam, know that configuration enforcement and decommissioning are key to secure system management. You may be given a scenario involving an outdated system, a configuration drift, or a forgotten virtual machine. Your task may be to identify the risk or recommend a mitigation plan. Focus on automation, audits, and secure data disposal as central elements of your answer.