Kali365 appeared in April 2026 and has already been used against hundreds of organisations. It’s sold on Telegram for around US$250 a month and does one thing well: it sits between your user and the real Microsoft 365 sign-in, lets them complete MFA normally, then steals the session token that proves they’re authenticated. From your logs, the sign-in looks clean. The attacker is now inside the mailbox, files and every SSO-connected app — no MFA prompt required.
This is adversary-in-the-middle, and it has gone from niche to commodity. AiTM attacks reportedly rose 146% year-on-year, with eleven phishing kits now competing on the open market. The defining feature is that they don’t attack MFA — they wait for it to succeed and steal what comes after.
MFA is still mandatory, but on its own it no longer stops this. The controls that do are phishing-resistant authentication (FIDO2 keys, passkeys, Windows Hello) that can’t be replayed against a fake page, Conditional Access that blocks unmanaged devices, and token-protection features that bind a session to its device so a stolen token is useless elsewhere.