incident-response-bec
Business Email Compromise and AiTM Analysis
Mission
Determine whether a Microsoft identity and mailbox event is consistent with BEC, AiTM session theft, or another compromise pattern. Keep the assessment advisory; final decision belongs to the human analyst.
Use when
- Suspicious sign-ins are paired with mailbox forwarding, inbox rules, or unexpected sent mail.
- A user reports phishing, strange mailbox behavior, or external recipients the user did not send to.
- The incident includes suspected session theft, token replay, or unauthorized app consent.
- The same workflow applies to non-Microsoft cases when equivalent sign-in and mailbox evidence exists.
Required context
- Preferred inputs: UPN, incident window, alert or incident ID, and any phishing message identifiers.
- If UPN is missing and Microsoft telemetry is required, ask for it before querying.
Investigation flow
- Confirm the compromise hypothesis
- identify the first suspicious sign-in or mailbox event
- note source IP, geo, ASN, device, client app, and MFA context
More from crtvrffnrt/skills
pentest-xss
Security assessment skill for Cross-Site Scripting (XSS) vulnerabilities. Use when investigating input sanitization, reflected, stored, DOM, or blind XSS. Focuses on discovery, exploitation, and payload optimization. Do not use for generic network recon or non-web injection types.
42pentest-exploit-execution-payload-control
Security assessment skill for deterministic exploit execution from validated primitives. Use when prompts include exploit implementation, payload hardening, chaining confirmed weaknesses, post-exploitation proof, or controlled impact demonstration. Do not use for early-stage reconnaissance, speculative hypothesis generation, or report-only requests.
34pentest-recon-surface-analysis
Security assessment skill for reconnaissance, endpoint/service enumeration, and attack-surface mapping. Use when prompts include recon, enumerate, map endpoints, discover assets, inventory interfaces, fingerprint technologies, or identify control-plane surfaces. Do not use when the request is exploit development, payload execution, or final report writing only.
33pentest-business-logic-abuse
Security assessment skill for business workflow abuse, state-machine manipulation, and control-plane logic flaws. Use when prompts include workflow bypass, race condition, replay, quota abuse, order-of-operations flaws, delegated execution abuse, or unauthorized state transitions. Do not use for pure input injection fuzzing, broad recon, or standalone report formatting tasks.
32pentest-gemini-az
Use when users need an Azure, Microsoft 365, or Entra ID companion that reads, lists, changes, and manages resources using the current Azure CLI session, with `az rest` as the default execution path.
29pentest-outbound-interaction-oob-detection
Security assessment skill for outbound interaction and out-of-band (OOB) validation. Use when prompts include SSRF callback confirmation, blind XSS beacons, webhook abuse, XXE/OOB behavior, DNS/HTTP callback correlation, or asynchronous server-side interaction proof. Do not use when vulnerabilities are fully in-band and require no external callback correlation.
28