Microsoft is facing increased exploitation of its OAuth 2.0 device authorization by hackers, bypassing multifactor authentication and hijacking enterprise accounts, as reported by Proofpoint on December 22, 2025. This critical security vulnerability has surged since September 2025. Concurrently, Microsoft announced the availability of new Microsoft 365 Copilot Business SKUs and promotions since December 1, 2025, alongside a global price update for commercial Microsoft 365 suites effective July 1, 2026, impacting its core productivity and AI offerings.