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)
Detection of Msiexec Abuse for Local, Network, and DLL Execution
Disable or Remove Feature or Program: Disable or remove unnecessary and potentially vulnerable software, features, or services to reduce the attack surface and prevent abuse by adversaries. This involves identifying software or features that are no longer needed or that could be exploited and ensuring they are either removed or properly disabled. This mitigation can be implemented through the following measures:
Remove Legacy Software:
Disable Unused Features:
Control Applications Installed by Users:
Remove Unnecessary Services:
Restrict Add-ons and Plugins:
Privileged Account Management: Privileged Account Management focuses on implementing policies, controls, and tools to securely manage privileged accounts (e.g., SYSTEM, root, or administrative accounts). This includes restricting access, limiting the scope of permissions, monitoring privileged account usage, and ensuring accountability through logging and auditing.This mitigation can be implemented through the following measures:
Account Permissions and Roles:
Credential Security:
Multi-Factor Authentication (MFA):
Privileged Access Management (PAM):
Auditing and Monitoring:
Just-In-Time Access:
Tools for Implementation
Privileged Access Management (PAM):
Credential Management:
Multi-Factor Authentication:
Linux Privilege Management:
Just-In-Time Access: