Researchers at Mitiga have uncovered a new Business Email Compromise (BEC) campaign that uses sophisticated spear phishing and Adversary-in-The-Middle (AiTM) tactics to gain access to corporate executives’ Microsoft 365 accounts.
According to researchers, the attackers are able to gain access to high-level accounts to monitor communications and intercept huge financial transactions.
In order to compromise the accounts of executives, the attackers send a phishing email pretending to come from DocuSign. DocuSign is a platform for managing electronic agreements that is commonly used in the business environment.
As soon as executives click on the “Review Document” button in the email, they are directed to a phishing page of a fake domain, where they are asked to log in to the Windows domain.
The attackers use evilginx2 proxy to carry out a so-called Adversary-in-the-Middle (AiTM attack, which allows the attackers to be in the middle between a phishing page and a legitimate login form for a specific company, making it easier for them to spoof login credentials.
The evilginx2 proxy steals the session cookie, which contained the credentials and MFA generated by the Windows domain. Attackers then load the stolen session cookies into their own browser to automatically log into the victim’s account and bypass MFA, as it has been verified by prior login.
The sources for this piece include an article in BleepingComputer.