Russian Hackers Exploit Microsoft OAuth to Target Ukraine Allies via Signal and WhatsApp

Multiple suspected Russia-linked threat actors are “aggressively” targeting individuals and organizations with ties to Ukraine and human rights with an aim to gain unauthorized access to Microsoft 365 accounts since early March 2025.

The highly targeted social engineering operations, per Volexity, are a shift from previously documented attacks that leveraged a technique known as device code phishing to achieve the same goals, indicating that indicating that the Russian adversaries behind these campaigns are actively refining their tradecraft to fly under the radar.