TA0005 · DEFENSE EVASION
Msiexec
Adversaries may abuse msiexec.exe to proxy execution of malicious payloads. Msiexec.exe is the command-line utility for the Windows Installer and is thus commonly associated with executing installation packages (.msi).
Detect it with
Use process monitoring to monitor the execution and arguments of msiexec.exe. Compare recent invocations of msiexec.exe with prior history of known good arguments and executed MSI files or DLLs to determine anomalous and potentially adversarial activity.
Why it matters on shift
Msiexec is one of the concrete ways adversaries achieve defense evasion. Recognising it in telemetry lets you name the technique in your ticket and pivot to what came before and after.
What to look for next
After defense evasion, the next tactic is usually Credential Access. Search your telemetry for the transition before closing the ticket.
Kill-chain context