Key takeaway
The name of a legitimate tool such as PowerShell, WMI or a process monitor does not explain its use. Check together who launched it, its parent process and the resources and hosts it accessed.
Distinguish three related concepts
Living off the land (LOTL) means misusing tools and services already available in a system. Lateral movement aims to access and control other devices and servers after initial entry, potentially using compromised accounts. Process manipulation covers changes to memory, execution or apparent relationships between processes. These are not malware families or synonyms, but they can be combined in one attack.
Process context says more than its name
PowerShell, WMI, PsExec, WinRM and remote desktop support legitimate Windows administration. LD_PRELOAD and ptrace also have legitimate Linux uses; investigate unexpected use and attempts to masquerade as a system service in context. DLL injection, replacement of process code (process hollowing) and takeover of an execution thread (thread hijacking) can leave evidence in memory and execution data. Parent-process spoofing can misrepresent relationships in the process tree. Process Hacker and System Informer are open-source system monitoring tools; a name alone does not establish malicious activity. Check the file source, signature and observed actions.
Make movement across the network visible
After reaching one device, an attacker may access others through a stolen account, password hash, weak permission, unpatched service or shared folder. Remote command execution and built-in administration tools can resemble normal work, so collect telemetry that links users, devices and processes. Compare expected access patterns with rare workstation-to-server connections, multiple logins by one account, unusual child processes, new services and unexpected outbound traffic.
Validate, contain and determine scope
Enable logging for process creation, command lines, authentication, network and endpoint events; correlate records by time, account and device. Limit administrative privileges and remote management, use MFA, restrict access to critical network segments and install updates to address vulnerabilities. If investigation indicates malicious use of a process or account, isolate the device under the response plan and rotate affected credentials from a trusted device. Identify the initial entry path and check other systems for related evidence. EDR and SIEM alerts start an investigation; the analyst selects actions based on available evidence and incident impact.