Gather Victim Network Information: DNS

Adversaries may gather information about the victim's DNS that can be used during targeting. DNS information may include a variety of details, including registered name servers as well as records that outline addressing for a target’s subdomains, mail servers, and other hosts. DNS, MX, TXT, and SPF records may also reveal the use of third party cloud and SaaS providers, such as Office 365, G Suite, Salesforce, or Zendesk.[1]

Adversaries may gather this information in various ways, such as querying or otherwise collecting details via DNS/Passive DNS. DNS information may also be exposed to adversaries via online or other accessible data sets (ex: Search Open Technical Databases).[2][3] Gathering this information may reveal opportunities for other forms of reconnaissance (ex: Search Open Technical Databases, Search Open Websites/Domains, or Active Scanning), establishing operational resources (ex: Acquire Infrastructure or Compromise Infrastructure), and/or initial access (ex: External Remote Services).

ID: T1590.002
Sub-technique of:  T1590
Tactic: Reconnaissance
Platforms: PRE
Contributors: Jannie Li, Microsoft Threat Intelligence Center (MSTIC)
Version: 1.1
Created: 02 October 2020
Last Modified: 21 October 2022

Mitigations

ID Mitigation Description
M1056 Pre-compromise

This 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.

Detection

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.

References