Breaches and incidentsBriefChecked against a primary source

Microsoft 365 “token spraying” campaign: 79 organizations

Huntress: between 14 Jul and 22 Sep 2026 an actor captured tokens via adversary-in-the-middle phishing (plus device-code phishing) and replayed them.

Disclosed

What happened

  • Huntress: between 14 Jul and 22 Sep 2026 an actor captured tokens via adversary-in-the-middle phishing (plus device-code phishing) and replayed them; at least 497 successful sign-ins against 200,000+ failed attempts across 79 organizations, with at least 48 rogue Entra devices registered. THN reports 97 compromised accounts; Huntress’s post does not state an account count. Huntress’s own Phase 3 sub-figures are internally inconsistent.
  • Techniques: T1557 AitM, token replay (T1550.001), rogue device registration, MFA method replacement within three hours at 19+ orgs, hidden inbox rules for payroll/deposit mail.
  • Attribution: none. Infrastructure links to 1337 Services GmbH hosting.

Sources

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