The first immediate action in an active incident iscontainment.Blocking the IP address (40.90.23.154)at the network edge prevents further communication with the malicious external server. Disabling PowerShell or removing local admin privileges are valid hardening steps, but containment by network control is the highest priority during an active compromise to stop data exfiltration or further command and control activity.
Reference:CompTIA SecurityX CAS-005, Domain 2.0: Apply incident response techniques focusing on immediate containment actions.