T1566.001 Spearphishing Attachment Mappings

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 to gain execution. 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 exploiting one application appear to be a file for a different one.

View in MITRE ATT&CK®

GCP Mappings

Capability ID Capability Description Mapping Type ATT&CK ID ATT&CK Name Notes
virus_total Virus Total technique_scores T1566.001 Spearphishing Attachment
Comments
VirusTotal, now part of Google Cloud, provides threat context and reputation data to help analyze suspicious files, URLs, domains, and IP addresses to detect cybersecurity threats.
References
beyondcorp_enterprise BeyondCorp Enterprise technique_scores T1566.001 Spearphishing Attachment
Comments
This control can help detect malicious links sent via phishing. The details include a list of samples of message delivery events. Each item in the list includes the date, message ID, subject hash, message body hash, username of the recipient, attachment hashes, and your primary domain name. This can be used to block senders.
References