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).(Citation: Microsoft msiexec) The Msiexec.exe binary may also be digitally signed by Microsoft.

Adversaries may abuse msiexec.exe to launch local or network accessible MSI files. Msiexec.exe can also execute DLLs.(Citation: LOLBAS Msiexec)(Citation: TrendMicro Msiexec Feb 2018) Since it may be signed and native on Windows systems, msiexec.exe can be used to bypass application control solutions that do not account for its potential abuse. Msiexec.exe execution may also be elevated to SYSTEM privileges if the <code>AlwaysInstallElevated</code> policy is enabled.(Citation: Microsoft AlwaysInstallElevated 2018)
Msiexec
source_name: mitre-attack  url: https://attack.mitre.org/techniques/T1218/007  external_id: T1218.007     source_name: TrendMicro Msiexec Feb 2018  description: Co, M. and Sison, G. (2018, February 8). Attack Using Windows Installer msiexec.exe leads to LokiBot. Retrieved April 18, 2019.  url: https://blog.trendmicro.com/trendlabs-security-intelligence/attack-using-windows-installer-msiexec-exe-leads-lokibot/     source_name: LOLBAS Msiexec  description: LOLBAS. (n.d.). Msiexec.exe. Retrieved April 18, 2019.  url: https://lolbas-project.github.io/lolbas/Binaries/Msiexec/     source_name: Microsoft msiexec  description: Microsoft. (2017, October 15). msiexec. Retrieved January 24, 2020.  url: https://docs.microsoft.com/en-us/windows-server/administration/windows-commands/msiexec     source_name: Microsoft AlwaysInstallElevated 2018  description: Microsoft. (2018, May 31). AlwaysInstallElevated. Retrieved December 14, 2020.  url: https://docs.microsoft.com/en-us/windows/win32/msi/alwaysinstallelevated     