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MITRE ATT&CK  /  T1566.001

T1566.001

Spearphishing Attachment

SUB-TECHNIQUE Initial Access

Description

Adversaries may send spearphishing emails with a malicious attachment in an attempt to gain access to victim systems. Spearphishing attachment is a specific variant of spearphishing. Spearphishing attachment is different from other forms of spearphishing in that it employs the use of malware attached to an email. All forms of spearphishing are electronically delivered social engineering targeted at a specific individual, company, or industry. In this scenario, adversaries attach a file to the spearphishing email and usually rely upon [User Execution](https://attack.mitre.org/techniques/T1204) to gain execution.(Citation: Unit 42 DarkHydrus July 2018) Spearphishing may also involve social engineering techniques, such as posing as a trusted source.There are many options for the attachment such as Microsoft Office documents, executables, PDFs, or archived files. Upon opening the attachment (and potentially clicking past protections), the adversary's payload exploits a vulnerability or directly executes on the user's system. The text of the spearphishing email usually tries to give a plausible reason why the file should be opened, and may explain how to bypass system protections in order to do so. The email may also contain instructions on how to decrypt an attachment, such as a zip file password, in order to evade email boundary defenses. Adversaries frequently manipulate file extensions and icons in order to make attached executables appear to be document files, or files expl…

Platforms

LinuxmacOSWindows

Mitigations

  • M1049 — Antivirus/Antimalware
  • M1018 — User Account Management
  • M1047 — Audit
  • M1031 — Network Intrusion Prevention
  • M1054 — Software Configuration
  • M1017 — User Training
  • M1021 — Restrict Web-Based Content
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Source: MITRE ATT&CK Enterprise matrix. View on attack.mitre.org →

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