Microsoft Warns of Large-Scale AiTM Phishing Attacks Against Over 10,000 Organizations

Microsoft on Tuesday disclosed that a large-scale phishing campaign targeted over 10,000 organizations since September 2021 by hijacking Office 365’s authentication process even on accounts secured with multi-factor authentication (MFA). “The attackers then used the stolen credentials and session cookies to access affected users’ mailboxes and perform follow-on business email compromise (BEC) campaigns against other…