Rarely seen sender address in the organization

Synopsis

Field	Value
Activation Period	14 Days
Training Period	30 Days
Test Period	N/A (single event)
Deduplication Period	1 Day
Required Data	Microsoft 365 Emails
Detection Modules	Email
ATT&CK Tactic	Reconnaissance (TA0043), Initial Access (TA0001)
ATT&CK Technique	Phishing for Information (T1598), Phishing (T1566)
Severity	Informational

Description

An email was received from a sender that has not been observed in the organization in the last 30 days.

Attacker's Goals

Aim to steal sensitive information

• Trick recipients into downloading harmful payloads
• Aim to gain unauthorized access to the organization's systems.

Investigative actions

• Check the email address for any unusual spellings, missing letters, or unknown domains.
• If the message contains attachments or links, scrutinize them for any suspicious indications.
• Monitor further actions taken, such as file downloads or access to potentially malicious links.