U.S. offers $10 million for hackers targeting WhatsApp, Signal users

Russian-linked threat groups UNC5792 and UNC4221 conducted sophisticated phishing campaigns impersonating support agents to steal Signal Backup Recovery Keys and compromise the private communications of U.S. officials and allied personnel. The root cause is a combination of insufficient security awareness — users were deceived by convincing social engineering — and inadequate access controls around sensitive account recovery mechanisms. This matters because encrypted messaging apps like Signal are often trusted implicitly, making users less vigilant about phishing attempts targeting them. With thousands of accounts already compromised, the breach of these channels poses serious national security and operational security risks.