Threats Tagged 'token replay'

Between July and September 2026, a sophisticated campaign targeted Microsoft 365 accounts using adversary-in-the-middle attacks and token replay techniques. Attackers captured sign-in sessions via AiTM relays and replayed stolen tokens from IP addresses linked to a German hosting provider. The campaign compromised 79 organizations with 497 successful sign-ins amid over 200,000 failed attempts. Malicious actors registered rogue Entra devices, replaced victim MFA methods, and created hidden inbox rules to conceal their activities. The operation evolved through four phases, rotating IP addresses and employing scripted token and browser session replay techniques. Compromised accounts were used for business email compromise, including sending payroll-related emails to external contacts.