Russian Hackers Exploit Microsoft OAuth to Target Ukraine Allies via Signal and WhatsApp
Apr 23, 2025
Device Security / Threat Intelligence
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 Russian adversaries are actively refining their tradecraft. "These recently observed attacks rely heavily on one-on-one interaction with a target, as the threat actor must both convince them to click a link and send back a Microsoft-generated code," security researchers Charlie Gardner, Josh Duke, Matthew Meltzer, Sean Koessel, Steven Adair, and Tom Lancaster said in an exhaustive analysis. At least two different threat clusters tracked as UTA0352 and UTA0355 are assessed to be behind the attacks, although the possibilit...