integratedsso[.]com

Microsoft has disclosed details of two campaigns in which threat actors are abusing third-party email delivery infrastructure to blast financial fraud scam messages and using passkey-themed social engineering to breach cloud environments. The first campaign, per the tech giant, involved sending over a million scam emails between August 3 and 5, 2026, by masquerading as chief executive officers (CEOs) of various target companies, aiming to persuade accounts payable departments at those firms to initiate Automated Clearing House (ACH) transfers for a supposed ServiceNow annual subscription. Evidence indicates that the operators behind the campaign have leveraged generative artificial intelligence (AI) to facilitate the creation of email templates and draft emails tailored to their recipients. The activity primarily singled out enterprise users in the U.S., spanning IT services, consumer goods, real estate, and discrete manufacturing sectors. "The campaign follows steps before and during the execution of the campaign: threat actors register impersonation domains, send executive-themed payment requests through trusted infrastructure, embed fabricated invoices and supporting conversations, and attempt to convince finance personnel to initiate ACH transfers," the Microsoft Security Research team said. "Unlike traditional invoice scams that rely on a single social engineering lure, this campaign layered executive impersonation, vendor branding, fabricated invoices, and supporting email conversations into a unified narrative intended to reduce recipient skepticism." The spoofed email messages contained a purported "approval" of the fake invoice to trick recipients into making payments to attacker-controlled accounts. To lend a veneer of legitimacy to the deception, the threat actor included a forged email thread along with the fabricated invoice. In a clever twist, the attackers identified CEOs, CFOs, and presidents at victim organizations and plugged their names and email addresses into the emails' signatures so that they look convincing to the targets. The campaign also heavily relied on bogus domains and content designed to impersonate trusted brands and individuals. Some of the registered domains are below - service-nowinc[.]com domainlify[.]net Passkey-Themed Social Engineering Leads to Cloud Compromise The second campaign documented by Redmond revolves around cloud-based intrusions targeting multiple accounts in which suspicious sign-ins are followed by the threat actors adding their own authentication methods, as well as high-volume Microsoft Graph activity, SharePoint and OneDrive downloads, and mailbox collection through REST APIs. The activity, which has been detected since May 2026, is consistent with "automated collection from compromised cloud identities using proxy-associated infrastructure," Microsoft said. The attack commonly begins with identity-focused social engineering. The threat actors call or message a user's personal phone number, while claiming to be from the organization's IT help desk and urging them to immediately update their passkey, multi-factor authentication (MFA), or single sign-on (SSO) configuration to avoid access disruptions. Unsuspecting employees are redirected to counterfeit websites that mimic the legitimate Microsoft sign-in experience via SMS messages sent to their personal devices. The end goal here is to use the pretext to guide them through adversary-in-the-middle (AitM) or device-code authentication flows and take control of their Microsoft accounts either by capturing the credentials or unknowingly granting access on the actor's behalf. "The actor appears to invest heavily in pre-attack research, likely gathering information about employees and organizational structure from public sources such as social networking and professional profiling platforms," Microsoft said. "In a smaller number of cases, actors take advantage of already compromised accounts to expand their reach" by sending similar passkey-themed messages via Microsoft Teams. What's more, the threat actor has been observed registering domains built around themes such as passkeys, SSO enrollment, account activation, and identity verification, at the same time including the target organization's name as a subdomain in the pattern: " . [.]com" - passkeyhelpdesk[.]com secure-passkey[.]com setupmypasskey[.]com add-passkey[.]com integratedsso[.]com oktasession[.]com syncmykey[.]com portalsetuphub[.]com It's worth noting that this modus operandi overlaps with a loose-knit cybercrime collective tracked by the cybersecurity community under the monikers Cordial Spider, O-UNC-045, PREY-0058, and UNC6671. The e-crime adversary has been described as a coordinated group of threat actors that operates multiple public extortion brands while sharing overlaps in the underlying phishing infrastructure and targeting footprint. "UNC6671 uses credential harvesting panels hosted on generic root domains masquerading as being related to passkeys, appending victim-specific subdomains to facilitate targeted voice phishing campaigns," Google-owned Mandiant noted last month. Although the exact nature of these connections is unclear, it's suspected that they have been driven by splintered affiliates retaining access to shared initial access playbooks or relying on the same commoditized phishing panels, voice-phishing callers, and shared infrastructure. Microsoft, for its part, has attributed the initial access activity observed in this campaign to a range of threat actors, including Storm-3121 and Storm-3032. While Storm-3121 carries out initial access activity leading to ShinyHunters and Falcon (aka CL-CRI-1182) extortion, Storm-3032 is its designation for UNC6671, which refers to a set of actors that broke off from the BlackFile (aka CL-CRI-1116) group and now operate under the Helix extortion brand. In at least one case investigated by Microsoft, the threat actors are said to have carried out an anomalous sign-in to Microsoft Office Home from an unmanaged device to expand their access to other applications like SharePoint Online and OneDrive through the Graph API and enumerate sensitive files and internal services. Another incident involved the use of a passkey lure to launch a device code phishing attack and gain control of a victim's account without having to steal their credentials or cookies, effectively getting around MFA safeguards. The third attack pattern detected by Microsoft employs compromised credentials, likely obtained from a prior event, to register their own phone-based method to bypass MFA and engage in reconnaissance and post-exploitation activity. "Following initial access, the actor's first objective was to transform a temporary compromise into a persistent foothold," the Windows maker said. "Rather than relying solely on stolen credentials, the actor enrolled an MFA method under their control, typically by registering a new phone number, authenticator application, or software-based one-time password (OTP) token." An advantage this actor-controlled second factor offers is that it allows the threat actor to sign-in into the victim's corporate account without their participation and maintain continued access in combination with unrevoked sessions or valid credentials. The various actions the threat actor can take upon establishing MFA persistence are as follows - Conduct extensive internal reconnaissance using the Graph API and inventory users, groups, permissions, resources, and accessible content across the tenant using the compromised identity. Inspect roles and high-value accounts and service identities for privilege escalation. Enumerate mailbox messages, folders, and attachment metadata for intelligence collection. Conduct high-volume access and download activity aimed at SharePoint Online and OneDrive for Business, and even Microsoft Exchange Online in some cases. Engage in sustained data exfiltration that lasts from several hours to multiple days depending on the volume of files and email content harvested from the compromised user. Deliberately rotate infrastructure across the attack lifecycle and use separate IP addresses for authentication, reconnaissance, and exfiltration activities so as to subvert network-based indicators. "The attack underscores a critical detection challenge: Microsoft Graph abuse rarely appears suspicious when viewed through a single API call," Microsoft said. "This attack serves as a strong example of why Graph activity must be assessed holistically, with emphasis on behavioral progression and cross-event correlation rather than individual API requests in isolation."

Microsoft says threat actors linked to ShinyHunters, Helix, and other extortion gangs are using passkey and single sign-on-themed social engineering attacks to compromise corporate Microsoft accounts and steal data from Microsoft 365 services. The activity has been observed since May 2026 and begins with the attackers researching targeted organizations and employees before calling or messaging victims while impersonating corporate IT help desks. The attackers tell employees that they must urgently update a passkey, multi-factor authentication (MFA), or single sign-on (SSO) configuration to avoid losing access to corporate systems. Victims are then directed to phishing sites designed to resemble legitimate Microsoft login pages, with links sometimes sent through SMS messages to employees' personal phones. Microsoft says that while the lures frequently revolve around passkeys, the attackers are not attempting to enroll a passkey. Instead, the passkey lures are used to trick targeted employees into signing in to adversary-in-the-middle (AiTM) phishing sites or using device-code authentication flows. AiTM attacks allow the threat actors to capture credentials and session tokens. Device code phishing tricks victims into authorizing access to their account via an attacker-controlled client using Microsoft's legitimate authentication pages. Microsoft says the attackers conduct extensive research before targeting employees. "The actor appears to invest heavily in pre-attack research, likely gathering information about employees and organizational structure from public sources such as social networking and professional profiling platforms," explains Microsoft. The threat actors also register phishing domains that combine company names with words related to passkeys, SSO, key synchronization, account setup, and identity verification. Some examples seen by Microsoft include: passkeyhelpdesk[.]com, secure-passkey[.]com, setupmypasskey[.]com, add-passkey[.]com, integratedsso[.]com, oktasession[.]com, keysyncos[.]com, and oskeysync[.]com. The attackers commonly place the victim company's name in a subdomain, such as company-name.secure-passkey[.]com, to make the phishing portal appear more convincing. Microsoft attributes the initial-access activity to multiple threat actors operating in the same extortion ecosystem, including groups it tracks as Storm-3121 and Storm-3032. Storm-3121 is associated with ShinyHunters and Falcon extortion, while Storm-3032 is believed to be tied to BlackFile extortion group members that now work under the Helix name. This activity overlaps with attacks previously documented by Google Threat Intelligence under the UNC6671 threat cluster. Google previously reported that UNC6671 uses phone-based social engineering and passkey-themed phishing infrastructure to compromise corporate identities before accessing enterprise cloud environments. Google has also linked UNC6671 activity to the same extortion gangs, including BlackFile, Helix, Falcon, Pink, and Redact. Mapping the Microsoft cloud after compromise Microsoft's new research gives a closer look at what happens inside Microsoft cloud environments after an account is compromised. In one investigated attack, Microsoft observed a suspicious sign-in from an unmanaged device to a Microsoft 365 service identified in Entra logs as "OfficeHome." OfficeHome is associated with the Office 365 portal's shared infrastructure, including Office applications accessed through a browser. After completing MFA, Microsoft says the attacker established a valid session and began checking what resources the compromised account could access. Within minutes, the session was used to access My Apps to see what applications are assigned to the account, My Profile for organizational information, Microsoft Approval Management, account-management interfaces, and My Sign-Ins. The attacker then accessed SharePoint Online, Outlook Web, Microsoft 365 collaboration and search services, an internal business application, and authentication flows associated with virtual desktops. Microsoft says the session remained active for approximately one hour while the attacker listed sensitive files and internal applications. In another attack, the passkey social engineering attacks led to device-code phishing, where the victim was convinced to enter a supplied code into Microsoft's legitimate authentication page. This issues an authentication token to the attacker-controlled OAuth application, allowing the threat actor to access the victim's account without completing another MFA challenge. The attacker now has access to all of the user's resources and connected SSO applications, whether they be Microsoft 365, Salesforce, Google Workspace, Dropbox, Adobe, SAP, Slack, Zendesk, Atlassian, and many others. In a third attack, the threat actor used previously compromised credentials for an account where it is believed an authenticator application had been registered days earlier. Microsoft says the threat actors then performed reconnaissance using an automated Node.js system and Microsoft Graph. After gaining access, the attackers often gain persistence by adding an MFA method they control. Microsoft says the attackers register new phone numbers, authenticator applications, and software-based one-time password tokens with compromised identities. This allows the threat actor to satisfy future MFA challenges without the victim's help, although Microsoft notes that the persistence does not survive a complete credential and session reset. The attackers then use Microsoft Graph to enumerate the victim's cloud environment. Microsoft saw Graph requests that enumerate: Organizations, licenses, and enabled services Users, groups, and group membership Directory roles and privileged accounts Registered authentication methods Applications and service principals OAuth permissions and application role assignments SharePoint sites, document libraries, folders, and files OneDrive resources Mail folders, messages, and attachments Microsoft says Graph requests such as /users, /groups, or /sites are common in enterprise environments, so they may not raise alarms. However, the activity becomes more suspicious when the same account, application, or access token rapidly moves across different resources, checks privileges and authentication settings, and then begins accessing email, attachments, files, or documents. After reconnaissance, the attackers move into cloud data collection from Microsoft 365. "Microsoft observed high-volume access and download activity targeting Microsoft SharePoint Online and Microsoft OneDrive for Business, with some intrusions extending into Microsoft Exchange Online through REST API-based access to email content," explained Microsoft. "Across SharePoint and OneDrive, the activity generated significant volumes of FileAccessed and FileDownloaded events, indicating systematic retrieval of cloud-hosted documents and organizational data." Microsoft says the activity appears automated, with connections using the python-httpx user agent during SharePoint and OneDrive access exfiltration. The attackers also appear to avoid rapid "smash-and-grab" exfiltration to avoid detection. Microsoft says the data theft instead lasts from a few hours to multiple days, with threat actors accessing fewer than 1,000 files or emails in a single hour to blend in with legitimate traffic. Microsoft recommends looking for unusual sign-ins followed by new MFA registrations, Microsoft Graph reconnaissance, and suspicious access to SharePoint, OneDrive, or Exchange. If an account is compromised, administrators should revoke active sessions and tokens, reset credentials, remove any authentication methods or mailbox rules added by the attackers, and require the user to re-register their authentication methods. Microsoft also recommends using phishing-resistant MFA, limiting sensitive cloud resources to managed devices, and disabling device-code authentication when it is not needed. Join Mikko Hyppönen and security leaders from the NFL, CHANEL, and Atlassian for a two-hour digital summit on what AI-speed attacks change, what defenders should stop doing, and how to validate, decide, fix, and re-validate at machine speed. Save your seat