ZeroHour
Threat actor

Storm-3121

3 mentions in 7 days · 3 in 30 days · 3 total · first seen · last

Timeline

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 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 Pose as IT Support to Hijack Microsoft 365 Accounts With Fake Passkey Alerts

Microsoft warns of vishing campaigns by Storm-3121 and Storm-3032 hijacking Microsoft 365 accounts via fake passkey alerts, adding attacker-controlled MFA and exfiltrating cloud data.

Microsoft Security Research has tracked the campaign since May 2026: callers posing as IT helpdesk staff tell employees to urgently update passkeys, MFA, or SSO settings via domains such as add-passkey[.]com and contoso[.]add-passkey[.]com. The lures lead to adversary-in-the-middle phishing or device-code authentication flows that yield credentials, session tokens, or OAuth tokens, after which attackers enroll their own MFA methods for persistence and run Microsoft Graph reconnaissance. They then collect SharePoint, OneDrive, and sometimes Exchange Online data at deliberately low rates (often under 1,000 files or messages per hour), with python-httpx seen in high-volume file access. Microsoft attributes initial access tradecraft to Storm-3121 and Storm-3032, linked respectively to ShinyHunters/Falcon and BlackFile/Helix extortion operations.

GBHackersupdated · 4d agofirst · 5d agoPhishing & fraud in the wild 13 sources1