Greatness has emerged as a phishing-as-a-service platform designed to steal Microsoft 365 access at a time when many organizations assume multi-factor authentication will stop account takeovers.

Rather than simply collecting a password, it can capture a valid sign-in token that lets an attacker enter cloud services as the victim.

A recent campaign used spoofed RingCentral voicemail and performance-review emails to reach inboxes.

The messages failed SPF, DKIM, and DMARC checks, yet domain-based safe-sender exclusions overrode those failures. This turns a convenience setting into an opening for attackers.

Analysts at ZeroBEC identified the activity while investigating four emails sent to a protected organization.

ZeroBEC said in a report shared with Cyber Security News (CSN) that the campaign combined real-time login relays, device-code phishing, and a centrally managed operator service delivered through Telegram.

Phishing email body as rendered in the inbox (Source - ZeroBec) — Phishing email body as rendered in the inbox (Source – ZeroBec)

The impact goes beyond a single stolen mailbox. A captured token can expose Outlook, Teams, SharePoint, OneDrive, calendars, contacts, and registered applications, then support further fraud or internal phishing across the tenant. The finding also reinforces why real-time AiTM phishing attacks deserve attention even where MFA is widely deployed.

Greatness PhaaS Bypasses Email Security and MFA

Greatness first appeared as a phishing kit, but it has grown into a service that gives operators ready-made lures, configurable domains, and tools to target Microsoft 365, iCloud, Yahoo, and Google Workspace.

Researchers saw operators use lookalike voicemail messages that urged recipients to open an alleged recording or appraisal notice.

The delivery chain begins with a trusted-brand impersonation and can pass through several redirects before landing on an attacker-controlled page.

GreatnessBot Telegram landing page (Source - ZeroBec) — GreatnessBot Telegram landing page (Source – ZeroBec)

It also checks for automated browsers and asks visitors to complete a human-verification step.

This layered approach can make routine scanning less useful and mirrors tactics described in recent MFA bypass campaigns.

At the final stage, Greatness acts as a live relay between the victim and Microsoft 365. The victim sees their organization’s authentic branding, enters a password, and completes the normal MFA prompt.

The relay then receives the issued authentication token, so the criminal does not need to defeat MFA directly.

That distinction matters during incident response. A password reset alone may not remove access because existing tokens and refresh tokens can still work.

Investigators should revoke active sessions in Entra ID, review OAuth application consent, and look for unfamiliar sign-ins that have already passed MFA, as SharePoint AiTM incident guidance has similarly stressed.

Greatness also offers a device-code route, using document-themed pages that persuade users to enter a code and approve a real sign-in.

This gives operators a second route when a live proxy is not suitable. The platform’s shared backend means campaign infrastructure may change while core operational patterns remain connected.

Defenders Need to Check Trust Rules

The campaign shows that email protection can fail through configuration, not a broken security product.

Organizations should audit every safe-sender list and transport-rule exclusion, especially for common software vendors. A domain should receive special treatment only when its mail also passes the expected authentication checks.

Vendor breach notices should trigger the same review. A customer list can reveal which companies are likely to trust a vendor domain, enabling convincing spoofing.

O365 Panel login page (Source - ZeroBec) — O365 Panel login page (Source – ZeroBec)

Teams can improve detection by checking whether the sender, claimed brand, and destination domain match, a pattern also seen when compromised Outlook accounts spread credential-stealing links.

Security teams should hunt for the listed domains, proxy addresses, unexpected Laravel cookies, and rapid access to several Microsoft 365 services from a new network.

They should also investigate MFA-approved logins from hosting or VPN infrastructure that does not match a user’s usual location or device.

After a suspected AiTM compromise, responders should revoke all active and refresh tokens, rotate credentials, inspect mailbox rules and OAuth consents, and review Microsoft Graph activity.

Blocking known infrastructure can help, but monitoring behavior is essential because phishing operators can replace domains and proxy nodes quickly.

Indicators of Compromise (IoCs):-

Type	Indicator	Description
Domain	searchbriefing.com	Initial click-tracking redirect
Domain	loading.finreportviewersoftware.sbs	Anti-analysis redirector
Domain	api-8g9ezadxs.onewayoutlook.one	Operator API endpoint
Domain	onewayoutolook.one	Greatness phishing domain
Domain	xdccoc.top	AiTM credential-theft domain
Domain	nawarra.top	AiTM phishing domain
Domain	saileventpartners.top	AiTM phishing domain
Domain	greatwallwebsite.blog	Greatness backend panel API
Domain	hashmiaghayi.cfd	Operator-provisioned phishing domain
Domain	addtoitinnew.sbs	Phishing domain exposed in panel
Domain	willgrantitinfewsecondafter.cfd	Phishing domain exposed in panel
Domain	lookatemailplease.one	Phishing domain exposed in panel
Domain	pleasebepatienttoload.sbs	Phishing domain exposed in panel
Domain	landfomarkpool.nl	Device-code phishing landing page
Domain	638uneconomical.birchibase.co.nl	Device-code phishing redirector
IP address	212.227.146.181	IONOS email origin used for spoofed sender activity
IP address	38.248.95.214	Common AiTM proxy and post-compromise login infrastructure
IP address	38.248.95.228	Candidate monitoring host with matching infrastructure fingerprint
IP address	38.248.95.236	Candidate monitoring host with matching infrastructure fingerprint
IP address	158.173.166.3	Post-compromise login and token-replay activity
IP address	46.173.240.225	Post-compromise VPN exit node
IP address	46.173.240.21	Post-compromise VPN exit node
IP address	46.173.240.190	Post-compromise VPN exit node
IP address	46.173.240.180	Post-compromise VPN exit node
IP address	46.173.240.127	Post-compromise VPN exit node
IP address	46.173.240.118	Post-compromise VPN exit node
IP address	46.173.240.17	Post-compromise VPN exit node
Email address	serviceringcentral.com	Spoofed sender address
Operator token	8g9ezadxs	Campaign token associated with redirector activity
Operator token	4am16l1tm	Campaign token tied to nawarra.top and saileventpartners.top
Cookie name	laravelsession	Laravel session cookie observed on suspicious infrastructure
Cookie name	XSRF-TOKEN	Laravel anti-forgery cookie observed on suspicious infrastructure
Web-page title	just a momment	Misspelled redirector title used as a hunting fingerprint
URL path	rgateclus	Redirector routing-path pattern
Subdomain pattern	api-[9-character-token].domain	Greatness operator API domain convention
Display name pattern	Your target-domain.com Performance Check	Spoofed email display-name pattern
Subject pattern	Action required: Review your performance appraisal	Observed urgency-themed phishing subject
Subject pattern	URGENT: Your Performance Review is Ready	Observed urgency-themed phishing subject
Subject pattern	Appraisal Awesomeness: Your Moment of Truth	Observed urgency-themed phishing subject

Note: IP addresses and domains are intentionally defanged (e.g., [.]) to prevent accidental resolution or hyperlinking. Re-fang only within controlled threat intelligence platforms such as MISP, VirusTotal, or your SIEM.

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