State actors are abusing OAuth device codes to get full M365 account access - here's what we know

Date:
Fri, 19 Dec 2025 14:15:00 +0000

Description:
Researchers spotted multiple groups using the same technique and believe it's only going to get worse.

FULL STORY

Cybercriminals, including state-sponsored threat actors, are increasingly abusing Microsofts OAuth 2.0 device code authentication flow to take over Microsoft 365 accounts.

This is according to a new report by cybersecurity researchers Proofpoint. In
a new paper published on December 18, researchers confirm that have seen a sharp escalation of social engineering attacks since September 2025, in which victims are tricked into granting access to their accounts.

The attack usually starts with a phishing email containing either a link or
QR code. Victims are then told that in order to view the contents, they need
to reauthenticate their account by entering a device code into Microsofts
login page.

Russians, Chinese, and others

Once they enter the code, the threat actors receive an access token tied to their account, not only giving them access, but enabling email monitoring, lateral movement, and more.

The login happens on a real Microsoft domain, Proofpoint further explains, which means that traditional phishing defenses and user awareness checks are mostly useless. The attackers arent actually stealing passwords , or MFA
codes, so no alarms are triggered there, either.

Proofpoint says there are multiple groups currently abusing this technique, including TA2723 (a financially motivated threat actor), UNK_AcademicFlare (a Russian state-sponsored threat actor targeting government and military email accounts for cyber-espionage purposes), and multiple groups from China.

It was also said that the criminals are using different phishing frameworks, such as SquarePhish 2 and Graphish, which automates device code abuse,
supports QR codes, and integrates with Azure app registrations. This lowers
the barrier to entry and allows even low-skilled threat actors to engage in attacks.

Proofpoint believes the abuse of OAuth and device code authentication is
likely to grow, especially as organizations adopt paswordless and FIDO-based authentication and recommends blocking device code flows via Conditional
Access where possible.

======================================================================
Link to news story: https://www.techradar.com/pro/security/state-actors-are-abusing-oauth-device-c odes-to-get-full-m365-account-access-heres-what-we-know

$$
--- SBBSecho 3.28-Linux
* Origin: Capitol City Online (1:2320/105)