Skip to content

T1589.002 Email Addresses

Adversaries may gather email addresses that can be used during targeting. Even if internal instances exist, organizations may have public-facing email infrastructure and addresses for employees.

Adversaries may easily gather email addresses, since they may be readily available and exposed via online or other accessible data sets (ex: Social Media or Search Victim-Owned Websites).45 Email addresses could also be enumerated via more active means (i.e. Active Scanning), such as probing and analyzing responses from authentication services that may reveal valid usernames in a system.3 For example, adversaries may be able to enumerate email addresses in Office 365 environments by querying a variety of publicly available API endpoints, such as autodiscover and GetCredentialType.21

Gathering this information may reveal opportunities for other forms of reconnaissance (ex: Search Open Websites/Domains or Phishing for Information), establishing operational resources (ex: Email Accounts), and/or initial access (ex: Phishing or Brute Force via External Remote Services).

Item Value
ID T1589.002
Sub-techniques T1589.001, T1589.002, T1589.003
Tactics TA0043
Platforms PRE
Version 1.2
Created 02 October 2020
Last Modified 21 October 2022

Procedure Examples

ID Name Description
S0677 AADInternals AADInternals can check for the existence of user email addresses using public Microsoft APIs.67
G0050 APT32 APT32 has collected e-mail addresses for activists and bloggers in order to target them with spyware.18
G1011 EXOTIC LILY EXOTIC LILY has gathered targeted individuals’ e-mail addresses through open source research and website contact forms.11
G0125 HAFNIUM HAFNIUM has collected e-mail addresses for users they intended to target.8
G1001 HEXANE HEXANE has targeted executives, human resources staff, and IT personnel for spearphishing.1716
G0094 Kimsuky Kimsuky has collected valid email addresses that were subsequently used in spearphishing campaigns.20
G1004 LAPSUS$ LAPSUS$ has gathered employee email addresses, including personal accounts, for social engineering and initial access efforts.10
G0032 Lazarus Group Lazarus Group collected email addresses belonging to various departments of a targeted organization which were used in follow-on phishing campaigns.19
G0059 Magic Hound Magic Hound has identified high-value email accounts in academia, journalism, NGO’s, foreign policy, and national security for targeting.1514
G0069 MuddyWater MuddyWater has specifically targeted government agency employees with spearphishing e-mails.21
G0034 Sandworm Team Sandworm Team has obtained valid emails addresses while conducting research against target organizations that were subsequently used in spearphishing campaigns.12
G0122 Silent Librarian Silent Librarian has collected e-mail addresses from targeted organizations from open Internet searches.9
G0127 TA551 TA551 has used spoofed company emails that were acquired from email clients on previously infected hosts to target other individuals.13


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
DS0029 Network Traffic Network Traffic Content


  1. Dr. Nestori Syynimaa. (2020, June 13). Just looking: Azure Active Directory reconnaissance as an outsider. Retrieved May 27, 2022. 

  2. gremwell. (2020, March 24). Office 365 User Enumeration. Retrieved May 27, 2022. 

  3. GrimHacker. (2017, July 24). Office365 ActiveSync Username Enumeration. Retrieved December 9, 2021. 

  4. Hackers Arise. (n.d.). Email Scraping and Maltego. Retrieved October 20, 2020. 

  5. Ng, A. (2019, January 17). Massive breach leaks 773 million email addresses, 21 million passwords. Retrieved October 20, 2020. 

  6. Dr. Nestori Syynimaa. (2018, October 25). AADInternals. Retrieved February 18, 2022. 

  7. Dr. Nestori Syynimaa. (2020, June 13). Just looking: Azure Active Directory reconnaissance as an outsider. Retrieved February 1, 2022. 

  8. Gruzweig, J. et al. (2021, March 2). Operation Exchange Marauder: Active Exploitation of Multiple Zero-Day Microsoft Exchange Vulnerabilities. Retrieved March 3, 2021. 

  9. DOJ. (2018, March 23). U.S. v. Rafatnejad et al . Retrieved February 3, 2021. 

  10. MSTIC, DART, M365 Defender. (2022, March 24). DEV-0537 Criminal Actor Targeting Organizations for Data Exfiltration and Destruction. Retrieved May 17, 2022. 

  11. Stolyarov, V. (2022, March 17). Exposing initial access broker with ties to Conti. Retrieved August 18, 2022. 

  12. Scott W. Brady. (2020, October 15). United States vs. Yuriy Sergeyevich Andrienko et al.. Retrieved November 25, 2020. 

  13. Duncan, B. (2021, January 7). TA551: Email Attack Campaign Switches from Valak to IcedID. Retrieved March 17, 2021. 

  14. Bash, A. (2021, October 14). Countering threats from Iran. Retrieved January 4, 2023. 

  15. Miller, J. et al. (2021, July 13). Operation SpoofedScholars: A Conversation with TA453. Retrieved August 18, 2021. 

  16. ClearSky Cyber Security . (2021, August). New Iranian Espionage Campaign By “Siamesekitten” - Lyceum. Retrieved June 6, 2022. 

  17. SecureWorks 2019, August 27 LYCEUM Takes Center Stage in Middle East Campaign Retrieved. 2019/11/19  

  18. Amnesty International. (2021, February 24). Vietnamese activists targeted by notorious hacking group. Retrieved March 1, 2021. 

  19. Vyacheslav Kopeytsev and Seongsu Park. (2021, February 25). Lazarus targets defense industry with ThreatNeedle. Retrieved October 27, 2021. 

  20. Jazi, H. (2021, June 1). Kimsuky APT continues to target South Korean government using AppleSeed backdoor. Retrieved June 10, 2021. 

  21. Mele, G. et al. (2021, February 10). Probable Iranian Cyber Actors, Static Kitten, Conducting Cyberespionage Campaign Targeting UAE and Kuwait Government Agencies. Retrieved March 17, 2021.