T1087Techniquediscoveryagent-callable
T1087Account Discovery
Platforms: ESXi · IaaS · Identity Provider · Linux · macOS · Office Suite · SaaS · Windows
ATT&CK version: v19.1
What it is
Adversaries may attempt to get a listing of valid accounts, usernames, or email addresses on a system or within a compromised environment. This information can help adversaries determine which accounts exist, which can aid in follow-on behavior such as brute-forcing, spear-phishing attacks, or account takeovers (e.g., [Valid Accounts](https://attack.mitre.org/techniques/T1078)).
Adversaries may use several methods to enumerate accounts, including abuse of existing tools, built-in commands, and potential misconfigurations that leak account names and roles or permissions in the targeted environment.
For examples, cloud environments typically provide easily accessible interfaces to obtain user lists.(Citation: AWS List Users)(Citation: Google Cloud - IAM Servie Accounts List API) On hosts, adversaries can use default [PowerShell](https://attack.mitre.org/techniques/T1059/001) and other command line functionality to identify accounts. Information about email addresses and accounts may also be extracted by searching an infected system’s files.