Why Traditional Phishing Has Changed
Cybercriminals are no longer focused solely on stealing usernames and passwords. Modern phishing campaigns are targeting something far more valuable: active authenticated sessions. Instead of trying to crack MFA or guess passwords, attackers wait until a user successfully logs in and then hijack the trusted session itself.
How AiTM Attacks Work
AiTM attacks use a live reverse proxy that sits between the user and the legitimate login service. Every login request, redirect, and MFA response passes through the attacker’s infrastructure in real time. To the user, the experience appears completely legitimate.
Why MFA Alone Isn’t Enough
MFA protects the authentication event itself, but once a user successfully signs in, the platform issues a session token or cookie that confirms the user has already been verified. If attackers steal that token, they can access the account without needing the password or MFA prompt again.
What Happens After the Session Is Stolen
Attackers operating inside a valid session often avoid traditional alerts because they appear as legitimate users. They may create inbox rules, monitor email conversations, register new MFA methods, or use the account to launch additional phishing attacks internally.
Reducing Your Risk
Businesses should strengthen conditional access policies, monitor suspicious post-login activity, and adopt phishing-resistant authentication methods such as passkeys and FIDO2 security keys. Employee awareness training focused on suspicious URLs also remains important.
Final Thoughts
MFA is still essential, but modern identity security requires protection beyond the login screen. Organizations that understand session theft are far better prepared to reduce the impact of AiTM attacks.