Device Code Phishing: Fake AI Event Invites Beat Your MFA
This is device code phishing: attackers send staff invitations to fake AI events and ask them to approve a Microsoft sign-in. The sign-in happens on Microsoft’s real website, so your multi-factor authentication (MFA) does not get in the way. If your business runs on Microsoft 365, one setting your IT provider can change this week removes most of the risk.
What actually happened
On 5 November 2026, Push Security published an analysis of fake event pages. Push detected and blocked visits in late October to pages posing as an OpenAI Academy livestream, a private SpaceX briefing and Anthropic at AWS re:Invent. Each asked for a work sign-in to claim a reward such as three months of ChatGPT Pro. The Microsoft route used a phishing service called Kali365, which shows a device code and sends the visitor to Microsoft’s genuine device login page. The Google route used a reverse proxy service called VoidProxy. Push gave no victim numbers.
Separately, ANY.RUN found 618 sandbox analyses of a similar kit, SkyW4lker, between June and 21 October 2026. Monthly submissions rose from 20 in June to 200 in September. The UK was among the most frequent submitting countries. These are samples, not confirmed victims.
Why device code phishing matters if you run a small or mid-sized business
Normal phishing steals a password on a fake page. Device code phishing does not. Microsoft built device code sign-in for things like meeting-room screens that cannot take a password easily. The device shows a short code, and a person enters it on a separate page to approve the sign-in.
The attacker starts that process themselves. Their page shows the victim a code and says “enter this to confirm your place”. The victim goes to Microsoft’s real page, types the code, signs in and passes MFA. They have just approved the attacker’s session. Microsoft then hands the attacker the tokens. No fake login page was ever needed, and MFA did exactly what it was designed to do.
The user does the approving. With those tokens an attacker can reach mail, files and any app that signs in through Microsoft.
The bait works because staff want to try new AI tools. The brand will change next week. The mechanism will not. Our guides to phishing-resistant MFA and MFA fatigue attacks explain how other attacks get around sign-in checks, and Microsoft 365 security basics covers the settings your IT provider will look at. We covered a similar session-theft lure in calendar invite phishing.
What to do this week
- Ask your IT provider to create an Entra Conditional Access policy that blocks the device code flow for all users, starting in report-only mode so nothing legitimate breaks.
- Ask them to check Entra sign-in logs for device code sign-ins in the last 30 days and tell you who used them and why.
- Set one staff rule today: never type a code into Microsoft that a web page, email or invitation handed you.
- Tell staff that a “free” AI subscription or an exclusive event asking for a work login is a red flag, and to report it to IT even if they clicked.
- Agree who revokes sessions and resets credentials if someone says they entered a code, so it takes minutes and not a day.
How Wolfcore helps
A policy is only proven when someone tests it. Our Phishy phishing simulation (see also what a phishing simulation is) lets you send realistic lures, including the “approve this code” kind, to your own staff. You see who stops and who reports, and you can fix the habit before a real attacker finds it. If you want to talk it through, you can get in touch.
Frequently asked questions
The attacker starts a Microsoft device code sign-in, shows the victim the code on a fake page and asks them to enter it on Microsoft’s real login page. The victim signs in and passes MFA, which approves the attacker’s session.
No. The victim completes MFA on Microsoft’s genuine page, so it does what it was built to do while approving the attacker.
Ask your IT provider to block the device code flow with an Entra Conditional Access policy, starting in report-only mode, and tell staff never to type a code that a web page, email or invitation gave them.
Ruben Selby
Founder and Lead Security Consultant, Wolfcore