Threat Huntmediumtest

Potential Data Exfiltration Over SMTP Via Send-MailMessage Cmdlet

Detects the execution of a PowerShell script with a call to the "Send-MailMessage" cmdlet along with the "-Attachments" flag. This could be a potential sign of data exfiltration via Email. Adversaries may steal data by exfiltrating it over an un-encrypted network protocol other than that of the existing command and control channel. The data may also be sent to an alternate network location from the main command and control server.

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Launch
François HubautCreated Mon Sep 26Updated Fri Nov 019a7afa56-4762-43eb-807d-c3dc9ffe211bwindows
Hunting Hypothesis
Log Source
WindowsPowerShell Script
ProductWindows← raw: windows
CategoryPowerShell Script← raw: ps_script

Definition

Requirements: Script Block Logging must be enabled

Detection Logic
Detection Logic1 selector
detection:
    selection:
        ScriptBlockText|contains: 'Send-MailMessage*-Attachments'
    condition: selection
False Positives
Unknown

False positive likelihood has not been assessed. Additional context may be needed during triage.

MITRE ATT&CK
Rule Metadata
Rule ID
9a7afa56-4762-43eb-807d-c3dc9ffe211b
Status
test
Level
medium
Type
Threat Hunt
Created
Mon Sep 26
Modified
Fri Nov 01
Path
rules-threat-hunting/windows/powershell/powershell_script/posh_ps_send_mailmessage.yml
Raw Tags
attack.exfiltrationattack.t1048.003detection.threat-hunting
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