Classification:

attack

Tactic:

TA0009-collection

Technique:

T1114-email-collection

VIEW RULE IN DATADOG VIEW SIGNALS

Goal

Detect when a user consents to an application associated with business email compromise.

Strategy

Monitor Microsoft 365 Exchange audit logs to look for the operation Consent to application.. Attackers who have gained unauthorized access to a victim’s account may add applications in order to collect emails or send out further phishing emails. In this detection, we try to identify the following applications:

• eM Client - a desktop email client with full Microsoft Office 365 synchronization.
• PerfectData Software - exports mailboxes for backup purposes.
• Newsletter Software Supermailer - email newsletter software to send out high volume emails.
• SigParser - email signature contact scraping and parsing.

Triage and response

1. Identify any additional unusual behaviors:
   • Previous failed logins.
   • Anomalous geo-location.
   • VPN usage.
2. Determine if there is a legitimate use case for the new application by contacting the user {{@usr.email}}.
3. If {{@usr.email}} is not aware of the application:
   • Investigate other activities performed by the user {{@usr.email}} using the Cloud SIEM - User Investigation dashboard.
   • Begin your organization’s incident response process and investigate.

Changelog

• 29 July 2024 - Added additional application ID for SigParser.
• 13 August 2024 - Added additional application to markdown.