Files
Anthropic-Cybersecurity-Skills/skills/analyzing-office365-audit-logs-for-compromise/SKILL.md
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mukul975 915ea611e5 Add 10 new cybersecurity skills with full folder anatomy
Skills added:
- implementing-privileged-access-workstation (IAM, PAW hardening)
- detecting-suspicious-oauth-application-consent (cloud security, Graph API)
- performing-hardware-security-module-integration (cryptography, PKCS#11)
- analyzing-android-malware-with-apktool (malware analysis, androguard)
- hunting-for-unusual-service-installations (threat hunting, T1543.003)
- detecting-shadow-it-cloud-usage (cloud security, proxy/DNS log analysis)
- performing-active-directory-forest-trust-attack (red team, impacket)
- implementing-deception-based-detection-with-canarytoken (deception, Canary API)
- analyzing-office365-audit-logs-for-compromise (cloud security, BEC detection)
- hunting-for-startup-folder-persistence (threat hunting, T1547.001)

Each skill includes SKILL.md, LICENSE, scripts/agent.py, references/api-reference.md
2026-03-11 00:47:03 +01:00

1.8 KiB

name, description, domain, subdomain, tags, version, author, license
name description domain subdomain tags version author license
analyzing-office365-audit-logs-for-compromise Parse Office 365 Unified Audit Logs via Microsoft Graph API to detect email forwarding rule creation, inbox delegation, suspicious OAuth app grants, and other indicators of account compromise. cybersecurity cloud-security
Office365
Microsoft-Graph
audit-logs
email-compromise
inbox-rules
OAuth
BEC
1.0 mahipal Apache-2.0

Analyzing Office 365 Audit Logs for Compromise

Overview

Business Email Compromise (BEC) attacks often leave traces in Office 365 audit logs: suspicious inbox rule creation, email forwarding to external addresses, mailbox delegation changes, and unauthorized OAuth application consent grants. This skill uses the Microsoft Graph API to query the Unified Audit Log, enumerate inbox rules across mailboxes, detect forwarding configurations, and identify compromised account indicators.

Prerequisites

  • Azure AD app registration with AuditLog.Read.All, MailboxSettings.Read, Mail.Read (application permissions)
  • Python 3.9+ with msal, requests
  • Client secret or certificate for authentication
  • Global Reader or Security Reader role

Steps

  1. Authenticate to Microsoft Graph using MSAL client credentials flow
  2. Query Unified Audit Log for suspicious operations (Set-Mailbox, New-InboxRule)
  3. Enumerate inbox rules across mailboxes and flag forwarding rules
  4. Detect mailbox delegation changes (Add-MailboxPermission)
  5. Identify OAuth consent grants to suspicious applications
  6. Check for suspicious sign-in patterns from audit logs
  7. Generate compromise indicator report with timeline

Expected Output

  • JSON report listing forwarding rules, delegation changes, OAuth grants, and suspicious audit events with risk scores
  • Timeline of compromise indicators with affected mailboxes