Detection Strategy for Phishing across platforms.

Technique Detected:  Phishing | T1566

ID: DET0070
Domains: Enterprise
Analytics: AN0188, AN0189, AN0190, AN0191, AN0192, AN0193
Version: 1.0
Created: 21 October 2025
Last Modified: 21 October 2025

Analytics

AN0188

Unusual inbound email activity where attachments or embedded URLs are delivered to users followed by execution of new processes or suspicious document behavior. Detection involves correlating email metadata, file creation, and network activity after a phishing message is received.

Log Sources
Data Component Name Channel
Application Log Content (DC0038) m365:unified Send/Receive: Emails with suspicious sender domains, spoofed headers, or anomalous attachment types
File Creation (DC0039) WinEventLog:Sysmon EventCode=11
Process Creation (DC0032) WinEventLog:Sysmon EventCode=1
Mutable Elements
Field Description
SuspiciousFileTypes Attachment types considered high risk (e.g., .exe, .js, .vbs, .scr, macro-enabled docs).
AllowedSenders Whitelist of known trusted senders to reduce false positives.

AN0189

Monitor for malicious payload delivery through phishing where attachments or URLs in email clients (e.g., Thunderbird, mutt) result in unusual file creation or outbound network connections. Focus on correlation between mail logs, file writes, and execution activity.

Log Sources
Data Component Name Channel
Application Log Content (DC0038) Application:Mail Inbound messages with anomalous headers, spoofed SPF/DKIM failures
Process Creation (DC0032) auditd:SYSCALL execve: Execution of scripts or binaries sourced from mail directories (/var/mail, ~/Maildir)
Mutable Elements
Field Description
MonitoredMailPaths System or user directories where emails/attachments are stored.
AttachmentHashBaseline Known good hashes for common business document templates.

AN0190

Detection of phishing through anomalous Mail app activity, such as attachments saved to disk and immediately executed, or Safari/Preview launching URLs and files linked from email messages. Correlate UnifiedLogs events with subsequent process execution.

Log Sources
Data Component Name Channel
Application Log Content (DC0038) macos:unifiedlog Inbound email activity with suspicious domains or mismatched sender information
Process Creation (DC0032) macos:unifiedlog Preview.app, Safari.app, or Mail.app spawning new processes outside normal patterns
Mutable Elements
Field Description
SuspiciousDomains List of domains known for phishing activity or suspicious sender infrastructure.
ExecutionDelayWindow Time threshold between file save and execution considered suspicious.

AN0191

Phishing via Office documents containing embedded macros or links that spawn processes. Detection relies on correlating Office application logs with suspicious child process execution and outbound network connections.

Log Sources
Data Component Name Channel
Application Log Content (DC0038) m365:unified FileAccessed: Access of email attachments by Office applications
Process Creation (DC0032) WinEventLog:Sysmon EventCode=1
Mutable Elements
Field Description
ParentProcessList Parent processes expected to execute child processes (e.g., Office apps).
MacroExecutionThreshold Threshold for number of macros executed before raising alerts.

AN0192

Phishing attempts targeting IdPs often manifest as anomalous login attempts from suspicious email invitations or fake SSO prompts. Detection correlates login flows, MFA bypass attempts, and anomalous geographic patterns following phishing email delivery.

Log Sources
Data Component Name Channel
Logon Session Creation (DC0067) azure:signinlogs Failed MFA attempts, unusual conditional access triggers, login attempts from unexpected IP ranges
Mutable Elements
Field Description
GeoAnomalyThreshold Allowed distance/time delta between user sign-ins.
MFABypassIndicators Signals of repeated or anomalous MFA failures linked to phishing campaigns.

AN0193

Phishing delivered via SaaS services (chat, collaboration platforms) where messages contain malicious URLs or attachments. Detect anomalous link clicks, suspicious file uploads, or token misuse after SaaS-based phishing attempts.

Log Sources
Data Component Name Channel
Application Log Content (DC0038) saas:collaboration MessagePosted: Suspicious links or attachment delivery via collaboration tools (Slack, Teams, Zoom)
Mutable Elements
Field Description
MonitoredSaaSApps Scope of SaaS platforms under phishing monitoring.
LinkInspectionPolicy Threshold for auto-expansion and detonation of URLs sent in SaaS messages.