Account Discovery

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).

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.[1][2] On hosts, adversaries can use default PowerShell 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.

ID: T1087
Sub-techniques:  T1087.001, T1087.002, T1087.003, T1087.004
Tactic: Discovery
Platforms: ESXi, IaaS, Identity Provider, Linux, Office Suite, SaaS, Windows, macOS
Contributors: Daniel Stepanic, Elastic; Microsoft Threat Intelligence Center (MSTIC); Travis Smith, Tripwire
Version: 2.6
Created: 31 May 2017
Last Modified: 24 October 2025

Procedure Examples

ID Name Description
C0062 Anthropic AI-orchestrated Campaign

During the Anthropic AI-orchestrated Campaign, the adversary used Claude Code to query internal database user account tables to enumerate accounts and identify high-privilege accounts within compromised environments.[3]

G0143 Aquatic Panda

Aquatic Panda used the last command in Linux environments to identify recently logged-in users on victim machines.[4]

G1016 FIN13

FIN13 has enumerated all users and their roles from a victim's main treasury system.[5]

S1229 Havoc

Havoc can identify privileged user accounts on infected systems.[6]

G1015 Scattered Spider

Scattered Spider has identified vSphere administrator accounts.[7]

S0445 ShimRatReporter

ShimRatReporter listed all non-privileged and privileged accounts available on the machine.[8]

C0024 SolarWinds Compromise

During the SolarWinds Compromise, APT29 obtained a list of users and their roles from an Exchange server using Get-ManagementRoleAssignment.[9]

S1239 TONESHELL

TONESHELL included functionality to retrieve a list of user accounts.[10]

S1065 Woody RAT

Woody RAT can identify administrator accounts on an infected machine.[11]

S0658 XCSSET

XCSSET attempts to discover accounts from various locations such as a user's Evernote, AppleID, Telegram, Skype, and WeChat data.[12]

Mitigations

ID Mitigation Description
M1028 Operating System Configuration

Prevent administrator accounts from being enumerated when an application is elevating through UAC since it can lead to the disclosure of account names. The Registry key is located HKLM\ SOFTWARE\Microsoft\Windows\CurrentVersion\Policies\CredUI\EnumerateAdministrators. It can be disabled through GPO: Computer Configuration > [Policies] > Administrative Templates > Windows Components > Credential User Interface: E numerate administrator accounts on elevation. [13]

M1018 User Account Management

Manage the creation, modification, use, and permissions associated to user accounts.

Detection Strategy

ID Name Analytic ID Analytic Description
DET0587 Enumeration of User or Account Information Across Platforms AN1612

Detection of processes performing local or domain account enumeration by invoking account directory queries or security APIs followed by structured output of account lists. The defender observes command execution or API invocation patterns that retrieve account information and produce enumeration artifacts shortly afterward.

AN1613

Enumeration of users and groups through suspicious shell commands or unauthorized access to /etc/passwd or /etc/shadow.

AN1614

Detection of account enumeration through directory service queries or system utilities accessing account metadata stores, followed by structured enumeration output.

AN1615

Detection of enumeration of identity entities through cloud provider APIs where principals retrieve account metadata such as IAM users or roles in rapid succession.

AN1616

Detection of identity directory enumeration through API calls or administrative queries retrieving multiple account objects within a short interval.

AN1617

Detection of enumeration activity when system processes query ESXi host account configuration or management APIs to retrieve user account listings.

AN1618

Account enumeration via bulk access to user directory features or hidden APIs.

AN1619

Account discovery via VBA macros, COM objects, or embedded scripting.

References