Adversaries may attempt to get a listing of local system accounts. This information can help adversaries determine which local accounts exist on a system to aid in follow-on behavior.
Commands such as <code>net user</code> and <code>net localgroup</code> of the Net utility and <code>id</code> and <code>groups</code> on macOS and Linux can list local users and groups.(Citation: Mandiant APT1)(Citation: id man page)(Citation: groups man page) On Linux, local users can also be enumerated through the use of the <code>/etc/passwd</code> file. On macOS, the <code>dscl . list /Users</code> command can be used to enumerate local accounts. On ESXi servers, the esxcli system account list command can list local user accounts.(Citation: Crowdstrike Hypervisor Jackpotting Pt 2 2021)
Local Account Enumeration Across Host Platforms
Operating System Configuration: Operating System Configuration involves adjusting system settings and hardening the default configurations of an operating system (OS) to mitigate adversary exploitation and prevent abuse of system functionality. Proper OS configurations address security vulnerabilities, limit attack surfaces, and ensure robust defense against a wide range of techniques. This mitigation can be implemented through the following measures:
Disable Unused Features:
Enforce OS-level Protections:
Secure Access Settings:
File System Hardening:
Secure Remote Access:
Harden Boot Configurations:
Regular Audits:
Tools for Implementation
Windows:
Linux/macOS:
Cross-Platform: