Which practice should incident responders avoid when restoring a system after an inappropriate usage incident?

The practice that incident responders should avoid when restoring a system after an inappropriate usage incident is using third-party security solutions to identify users. This approach poses significant risks for several reasons. First, third-party security solutions may not be fully vetted or compliant with the organization's policies and standards, which can introduce additional vulnerabilities into the system. Moreover, relying on these external tools may compromise the integrity and privacy of sensitive user data, particularly if the tools require access to comprehensive system information.

Additionally, the improper usage incident could be indicative of deeper systemic vulnerabilities or user behavior issues that are not addressed simply by identifying users with external tools. Focusing on restoring the system securely through established internal protocols is crucial to maintaining a secure environment and ensuring all users are treated in accordance with company policies and legal frameworks.

In contrast, conducting a comprehensive system audit, restoring from a clean backup, and implementing immediate security patches are all proactive practices that enhance system security, ensure integrity, and help mitigate the potential for further incidents. These actions enable a thorough understanding of what happened, close any security gaps, and provide a clean slate from which to restore normal operations.