Gather Victim Host Information: Client Configurations

Adversaries may gather information about the victim's client configurations that can be used during targeting. Information about client configurations may include a variety of details and settings, including operating system/version, virtualization, architecture (ex: 32 or 64 bit), language, and/or time zone.

Adversaries may gather this information in various ways, such as direct collection actions via Active Scanning (ex: listening ports, server banners, user agent strings) or Phishing for Information. Adversaries may also compromise sites then include malicious content designed to collect host information from visitors.[1] Information about the client configurations may also be exposed to adversaries via online or other accessible data sets (ex: job postings, network maps, assessment reports, resumes, or purchase invoices). Gathering this information may reveal opportunities for other forms of reconnaissance (ex: Search Open Websites/Domains or Search Open Technical Databases), establishing operational resources (ex: Develop Capabilities or Obtain Capabilities), and/or initial access (ex: Supply Chain Compromise or External Remote Services).

ID: T1592.004
Sub-technique of:  T1592
Tactic: Reconnaissance
Platforms: PRE
Version: 1.1
Created: 02 October 2020
Last Modified: 17 October 2021

Procedure Examples

ID Name Description

HAFNIUM has interacted with Office 365 tenants to gather details regarding target's environments.[2]


ID Mitigation Description
M1056 Pre-compromise

This technique cannot be easily mitigated with preventive controls since it is based on behaviors performed outside of the scope of enterprise defenses and controls. Efforts should focus on minimizing the amount and sensitivity of data available to external parties.


ID Data Source Data Component
DS0035 Internet Scan Response Content

Internet scanners may be used to look for patterns associated with malicious content designed to collect client configuration information from visitors.[3][1]

Much of this activity may have a very high occurrence and associated false positive rate, as well as potentially taking place outside the visibility of the target organization, making detection difficult for defenders. Detection efforts may be focused on related stages of the adversary lifecycle, such as during Initial Access.