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Microsoft Graph

6 mentions in 7 days · 7 in 30 days · 7 total · first seen · last

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Passkey-themed phishing attacks lead to Microsoft 365 data theft

Microsoft links ShinyHunters- and Helix-affiliated actors to passkey-themed vishing and device-code phishing that compromises Microsoft 365 accounts and steals cloud data.

Microsoft attributes passkey- and SSO-themed social engineering activity, observed since May 2026, to Storm-3121 (linked to ShinyHunters and Falcon) and Storm-3032 (tied to BlackFile members now operating as Helix). Attackers impersonate corporate IT help desks by phone or SMS, urging fake passkey, MFA, or SSO updates and directing victims to adversary-in-the-middle phishing pages or device-code authentication flows that yield credentials, session tokens, and OAuth tokens. Post-compromise behavior includes Microsoft Graph enumeration of users, SharePoint, and OAuth grants, plus persistence via attacker-controlled MFA methods. Google Threat Intelligence tracks related activity as UNC6671, linked to the BlackFile, Helix, Falcon, Pink, and Redact extortion gangs.

BleepingComputer · 4d agoPhishing & fraud in the wild 13 sources

Attackers use passkey-themed scams to hijack Microsoft 365 accounts

Microsoft tracks ongoing M365 cloud intrusions since May using passkey-themed helpdesk vishing, AiTM phishing, and device-code abuse.

Microsoft Security Research has tracked active cloud intrusions since May in which attackers posing as IT helpdesk staff lured employees with fake passkey/MFA enrollment requests. Attacks used adversary-in-the-middle phishing pages, device-code authentication flows, and Teams messages from compromised accounts. Attackers registered their own MFA methods, enumerated tenants via Microsoft Graph, and accessed SharePoint, OneDrive, and Exchange Online data, throttling activity below 1000 files/emails per hour.

CSO Onlineupdated · 4d agofirst · 4d agoThreat actor in the wild 13 sources1

Voice Callers Exploit BYOD to Reach Microsoft 365, Corporate Data

Threat actors use voice calls and Microsoft Graph API via BYOD devices to access Microsoft 365, then sell access to extortion groups like ShinyHunters.

Dark Reading reports that threat actors are exploiting BYOD scenarios and voice-based social engineering to gain access to Microsoft 365 environments and corporate data. The actors use Microsoft's Graph API to identify lucrative targets within compromised tenants. Access is then passed to extortion groups such as ShinyHunters, which is known for large-scale data theft and extortion campaigns. The source text is a brief summary, so victim counts and full scope are not specified.

Dark Readingupdated · 4d agofirst · 5d agoThreat actor in the wild 13 sources

Attackers call employees’ personal phones to break into Microsoft 365 accounts

Microsoft tracks vishing campaigns by Storm-3121 and Storm-3032 that impersonate IT staff, phish Microsoft 365 credentials, and steal cloud data.

Microsoft Security Research has tracked a campaign since May 2026 in which attackers call or text employees' personal phones posing as IT staff, using passkey/MFA/SSO lures to run adversary-in-the-middle phishing or device-code authentication flows. Attackers register their own MFA methods for durable persistence, abuse Microsoft Graph for tenant discovery, and download SharePoint, OneDrive, and Exchange data below 1,000 files or emails per hour to avoid detection. Microsoft attributes initial access to actors including Storm-3121, which feeds ShinyHunters and Falcon extortion operations, and Storm-3032, the Helix extortion operation descended from BlackFile.

Help Net Securityupdated · 4d agofirst · 5d agoPhishing & fraud in the wild 13 sources1

Hackers Use Passkey-Themed Phishing to Hijack Microsoft 365 Accounts and Steal Cloud Data

Microsoft reports passkey-themed phishing campaigns hijacking Microsoft 365 accounts via AiTM and device-code flows, then exfiltrating cloud data.

Microsoft researchers identified passkey-themed phishing across cloud intrusions observed since May 2026, where callers posing as IT support direct victims to lookalike sign-in pages. The flows include adversary-in-the-middle phishing and device-code authentication, letting attackers capture usable sessions even when MFA succeeds, followed by rogue MFA registration for persistence. Attackers enumerate tenants via Microsoft Graph and collect SharePoint, OneDrive, and Exchange data at rates below 1,000 items per hour; lure domains include passkeyhelpdesk.com and setupmypasskey.com.

Cyber Security Newsupdated · 4d agofirst · 5d agoPhishing & fraud in the wild 13 sources

Passkey-themed social engineering leads to identity and cloud compromise

Microsoft tracks ongoing cloud intrusions where passkey-themed helpdesk lures enable AiTM credential theft, MFA persistence, and SharePoint data theft.

Microsoft Security Research is tracking active cloud-based intrusions, observed since May 2026, that begin with helpdesk impersonation calls and SMS lures urging urgent passkey, MFA, or SSO updates. The lures lead to adversary-in-the-middle phishing or device-code authentication flows that capture credentials and session tokens or grant actor access, after which the actors add authentication methods, conduct Microsoft Graph reconnaissance, and download SharePoint and OneDrive content via REST APIs. Phishing domains embed victim organization names as subdomains (e.g., contoso.add-passkey[.]com), are often registered with Nicenic, and go operational within hours. Microsoft advises revoking sessions and removing unauthorized authentication methods for confirmed compromises.

Microsoft Security Blogupdated · 4d agofirst · 6d agoThreat actor in the wild 13 sources2

CISA Red Team Fully Compromised Two Critical Infrastructure Orgs

CISA red teams achieved full domain and cloud compromise at two critical infrastructure orgs; one SOC never detected the intrusion.

CISA advisory AA26-237A documents two simultaneous red team assessments. Organization A (Government Services sector) missed the intrusion entirely, as default credentials on a web app, ADCS ESC1 abuse, and thousands of false-positive alerts let the red team reach sensitive business systems and read SOC email. Organization B (Water/Wastewater sector) detected, isolated, and reimaged hosts quickly, but both orgs lacked Conditional Access for workload identities, and B still exposed DCSync, Golden Ticket, and OT network attack paths.

Security Affairs · 20d agoAdvisory1